Index: clang-tools-extra/clang-tidy/add_new_check.py
===================================================================
--- clang-tools-extra/clang-tidy/add_new_check.py
+++ clang-tools-extra/clang-tidy/add_new_check.py
@@ -278,8 +278,9 @@
 # Adds a test for the check.
 def write_test(module_path, module, check_name, test_extension):
   check_name_dashes = module + '-' + check_name
-  filename = os.path.normpath(os.path.join(module_path, '../../test/clang-tidy/checkers',
-                                           check_name_dashes + '.' + test_extension))
+  filename = os.path.normpath(os.path.join(
+    module_path, '..', '..', 'test', 'clang-tidy', 'checkers',
+    module, check_name + '.' + test_extension))
   print('Creating %s...' % filename)
   with io.open(filename, 'w', encoding='utf8', newline='\n') as f:
     f.write("""// RUN: %%check_clang_tidy %%s %(check_name_dashes)s %%t
Index: clang-tools-extra/docs/clang-tidy/Contributing.rst
===================================================================
--- clang-tools-extra/docs/clang-tidy/Contributing.rst
+++ clang-tools-extra/docs/clang-tidy/Contributing.rst
@@ -582,7 +582,7 @@
 substitutions and distinct function and variable names in the test code.
 
 Here's an example of a test using the ``check_clang_tidy.py`` script (the full
-source code is at `test/clang-tidy/google-readability-casting.cpp`_):
+source code is at `test/clang-tidy/checkers/google/readability-casting.cpp`_):
 
 .. code-block:: c++
 
@@ -632,12 +632,18 @@
    expansions/instantiations.
 
 If you need multiple files to exercise all the aspects of your check, it is
-recommended you place them in a subdirectory named for the check under ``Inputs``.
-This keeps the test directory from getting cluttered.
+recommended you place them in a subdirectory named for the check under the ``Inputs``
+directory for the module containing your check.  This keeps the test directory from
+getting cluttered.
+
+If you need to validate how your check interacts with system header files, a set
+of simulated system header files is located in the ``checkers/Inputs/Headers``
+directory.  The path to this directory is available in a lit test with the variable
+``%clang_tidy_headers``.
 
 .. _lit: https://llvm.org/docs/CommandGuide/lit.html
 .. _FileCheck: https://llvm.org/docs/CommandGuide/FileCheck.html
-.. _test/clang-tidy/google-readability-casting.cpp: https://reviews.llvm.org/diffusion/L/browse/clang-tools-extra/trunk/test/clang-tidy/google-readability-casting.cpp
+.. _test/clang-tidy/checkers/google/readability-casting.cpp: https://github.com/llvm/llvm-project/blob/main/clang-tools-extra/test/clang-tidy/checkers/google/readability-casting.cpp
 
 Out-of-tree check plugins
 -------------------------
Index: clang-tools-extra/test/clang-tidy/checkers/altera/kernel-name-restriction.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/altera/kernel-name-restriction.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/altera/kernel-name-restriction.cpp
@@ -1,5 +1,5 @@
-// RUN: %check_clang_tidy %s altera-kernel-name-restriction %t -- -- -I%S/Inputs/altera-kernel-name-restriction
-// RUN: %check_clang_tidy -check-suffix=UPPERCASE %s altera-kernel-name-restriction %t -- -- -I%S/Inputs/altera-kernel-name-restriction/uppercase -DUPPERCASE
+// RUN: %check_clang_tidy %s altera-kernel-name-restriction %t -- -- -I%S/Inputs/kernel-name-restriction
+// RUN: %check_clang_tidy -check-suffix=UPPERCASE %s altera-kernel-name-restriction %t -- -- -I%S/Inputs/kernel-name-restriction/uppercase -DUPPERCASE
 
 #ifdef UPPERCASE
 // The warning should be triggered regardless of capitalization
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/argument-comment.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/argument-comment.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/argument-comment.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s bugprone-argument-comment %t -- -- -I %S/Inputs/bugprone-argument-comment
+// RUN: %check_clang_tidy %s bugprone-argument-comment %t -- -- -I %S/Inputs/argument-comment
 
 // FIXME: clang-tidy should provide a -verify mode to make writing these checks
 // easier and more accurate.
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-in-initialization-strlen.c
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-in-initialization-strlen.c
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-in-initialization-strlen.c
@@ -1,5 +1,5 @@
 // RUN: %check_clang_tidy %s bugprone-not-null-terminated-result %t -- \
-// RUN: -- -std=c11 -I %S/Inputs/bugprone-not-null-terminated-result
+// RUN: -- -std=c11 -I %S/Inputs/not-null-terminated-result
 
 #include "not-null-terminated-result-c.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-memcpy-before-safe.c
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-memcpy-before-safe.c
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-memcpy-before-safe.c
@@ -2,7 +2,7 @@
 // RUN: -config="{CheckOptions: \
 // RUN: [{key: bugprone-not-null-terminated-result.WantToUseSafeFunctions, \
 // RUN:   value: true}]}" \
-// RUN: -- -std=c11 -I %S/Inputs/bugprone-not-null-terminated-result
+// RUN: -- -std=c11 -I %S/Inputs/not-null-terminated-result
 
 #include "not-null-terminated-result-c.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-memcpy-safe-cxx.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-memcpy-safe-cxx.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-memcpy-safe-cxx.cpp
@@ -1,5 +1,5 @@
 // RUN: %check_clang_tidy %s bugprone-not-null-terminated-result %t -- \
-// RUN: -- -std=c++11 -I %S/Inputs/bugprone-not-null-terminated-result
+// RUN: -- -std=c++11 -I %S/Inputs/not-null-terminated-result
 
 #include "not-null-terminated-result-cxx.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-memcpy-safe-other.c
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-memcpy-safe-other.c
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-memcpy-safe-other.c
@@ -1,5 +1,5 @@
 // RUN: %check_clang_tidy %s bugprone-not-null-terminated-result %t -- \
-// RUN: -- -std=c11 -I %S/Inputs/bugprone-not-null-terminated-result
+// RUN: -- -std=c11 -I %S/Inputs/not-null-terminated-result
 
 #include "not-null-terminated-result-c.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-memcpy-safe.c
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-memcpy-safe.c
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-memcpy-safe.c
@@ -1,5 +1,5 @@
 // RUN: %check_clang_tidy %s bugprone-not-null-terminated-result %t -- \
-// RUN: -- -std=c11 -I %S/Inputs/bugprone-not-null-terminated-result
+// RUN: -- -std=c11 -I %S/Inputs/not-null-terminated-result
 
 #include "not-null-terminated-result-c.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-stdc-want-lib-ext1-not-a-literal.c
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-stdc-want-lib-ext1-not-a-literal.c
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-stdc-want-lib-ext1-not-a-literal.c
@@ -1,5 +1,5 @@
 // RUN: %check_clang_tidy %s bugprone-not-null-terminated-result %t -- \
-// RUN: -- -std=c11 -I %S/Inputs/bugprone-not-null-terminated-result
+// RUN: -- -std=c11 -I %S/Inputs/not-null-terminated-result
 
 #include "not-null-terminated-result-c.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-strlen.c
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-strlen.c
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-strlen.c
@@ -1,5 +1,5 @@
 // RUN: %check_clang_tidy %s bugprone-not-null-terminated-result %t -- \
-// RUN: -- -std=c11 -I %S/Inputs/bugprone-not-null-terminated-result
+// RUN: -- -std=c11 -I %S/Inputs/not-null-terminated-result
 
 // FIXME: Something wrong with the APInt un/signed conversion on Windows:
 // in 'strncmp(str6, "string", 7);' it tries to inject '4294967302' as length.
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-undef-stdc-want-lib-ext1.c
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-undef-stdc-want-lib-ext1.c
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-undef-stdc-want-lib-ext1.c
@@ -1,5 +1,5 @@
 // RUN: %check_clang_tidy %s bugprone-not-null-terminated-result %t -- \
-// RUN: -- -std=c11 -I %S/Inputs/bugprone-not-null-terminated-result
+// RUN: -- -std=c11 -I %S/Inputs/not-null-terminated-result
 
 #include "not-null-terminated-result-c.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-wcslen.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-wcslen.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-wcslen.cpp
@@ -1,5 +1,5 @@
 // RUN: %check_clang_tidy %s bugprone-not-null-terminated-result %t -- \
-// RUN: -- -std=c++11 -I %S/Inputs/bugprone-not-null-terminated-result
+// RUN: -- -std=c++11 -I %S/Inputs/not-null-terminated-result
 
 // FIXME: Something wrong with the APInt un/signed conversion on Windows:
 // in 'wcsncmp(wcs6, L"string", 7);' it tries to inject '4294967302' as length.
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-wmemcpy-safe-cxx.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-wmemcpy-safe-cxx.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/not-null-terminated-result-wmemcpy-safe-cxx.cpp
@@ -1,5 +1,5 @@
 // RUN: %check_clang_tidy %s bugprone-not-null-terminated-result %t -- \
-// RUN: -- -std=c++11 -I %S/Inputs/bugprone-not-null-terminated-result
+// RUN: -- -std=c++11 -I %S/Inputs/not-null-terminated-result
 
 #include "not-null-terminated-result-cxx.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/reserved-identifier-invert.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/reserved-identifier-invert.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/reserved-identifier-invert.cpp
@@ -3,8 +3,8 @@
 // RUN:     {key: bugprone-reserved-identifier.Invert, value: true}, \
 // RUN:     {key: bugprone-reserved-identifier.AllowedIdentifiers, value: std;reference_wrapper;ref;cref;type;get}, \
 // RUN:   ]}' -- \
-// RUN:   -I%S/Inputs/bugprone-reserved-identifier \
-// RUN:   -isystem %S/Inputs/bugprone-reserved-identifier/system
+// RUN:   -I%S/Inputs/reserved-identifier \
+// RUN:   -isystem %S/Inputs/reserved-identifier/system
 
 namespace std {
 
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/reserved-identifier.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/reserved-identifier.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/reserved-identifier.cpp
@@ -1,6 +1,6 @@
 // RUN: %check_clang_tidy %s bugprone-reserved-identifier %t -- -- \
-// RUN:   -I%S/Inputs/bugprone-reserved-identifier \
-// RUN:   -isystem %S/Inputs/bugprone-reserved-identifier/system
+// RUN:   -I%S/Inputs/reserved-identifier \
+// RUN:   -isystem %S/Inputs/reserved-identifier/system
 
 // no warnings expected without -header-filter=
 #include "user-header.h"
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/signal-handler-minimal.c
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/signal-handler-minimal.c
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/signal-handler-minimal.c
@@ -1,7 +1,7 @@
 // RUN: %check_clang_tidy %s bugprone-signal-handler %t \
 // RUN: -config='{CheckOptions: \
 // RUN:  [{key: bugprone-signal-handler.AsyncSafeFunctionSet, value: "minimal"}]}' \
-// RUN: -- -isystem %S/Inputs/Headers
+// RUN: -- -isystem %clang_tidy_headers
 
 #include "signal.h"
 #include "stdlib.h"
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/signal-handler-posix.c
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/signal-handler-posix.c
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/signal-handler-posix.c
@@ -1,7 +1,7 @@
 // RUN: %check_clang_tidy %s bugprone-signal-handler %t \
 // RUN: -config='{CheckOptions: \
 // RUN:  [{key: bugprone-signal-handler.AsyncSafeFunctionSet, value: "POSIX"}]}' \
-// RUN: -- -isystem %S/Inputs/Headers
+// RUN: -- -isystem %clang_tidy_headers
 
 #include "signal.h"
 #include "stdlib.h"
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/signal-handler.c
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/signal-handler.c
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/signal-handler.c
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s bugprone-signal-handler %t -- -- -isystem %S/Inputs/Headers
+// RUN: %check_clang_tidy %s bugprone-signal-handler %t -- -- -isystem %clang_tidy_headers
 
 #include "signal.h"
 #include "stdlib.h"
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/suspicious-include.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/suspicious-include.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/suspicious-include.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s bugprone-suspicious-include %t -- -- -isystem %S/Inputs/Headers -fmodules
+// RUN: %check_clang_tidy %s bugprone-suspicious-include %t -- -- -isystem %clang_tidy_headers -fmodules
 
 // clang-format off
 
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/unchecked-optional-access.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone/unchecked-optional-access.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/unchecked-optional-access.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s bugprone-unchecked-optional-access %t -- -- -I %S/Inputs/
+// RUN: %check_clang_tidy %s bugprone-unchecked-optional-access %t -- -- -I %S/Inputs/unchecked-optional-access
 
 #include "absl/types/optional.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/cert/dcl58-cpp.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/cert/dcl58-cpp.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/cert/dcl58-cpp.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s cert-dcl58-cpp %t -- -- -std=c++1z -I %S/Inputs/Headers
+// RUN: %check_clang_tidy %s cert-dcl58-cpp %t -- -- -std=c++1z -I %clang_tidy_headers
 
 #include "system-header-simulation.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/cert/uppercase-literal-suffix-integer.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/cert/uppercase-literal-suffix-integer.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/cert/uppercase-literal-suffix-integer.cpp
@@ -3,7 +3,7 @@
 // RUN: clang-tidy %t.cpp -checks='-*,cert-dcl16-c' -fix -- -I %S
 // RUN: clang-tidy %t.cpp -checks='-*,cert-dcl16-c' -warnings-as-errors='-*,cert-dcl16-c' -- -I %S
 
-#include "readability-uppercase-literal-suffix.h"
+#include "../readability/uppercase-literal-suffix.h"
 
 void integer_suffix() {
   static constexpr auto v0 = __LINE__; // synthetic
Index: clang-tools-extra/test/clang-tidy/checkers/google/objc-function-naming.m
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/google/objc-function-naming.m
+++ clang-tools-extra/test/clang-tidy/checkers/google/objc-function-naming.m
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s google-objc-function-naming %t -- -- -isystem %S/Inputs/Headers
+// RUN: %check_clang_tidy %s google-objc-function-naming %t -- -- -isystem %clang_tidy_headers
 
 #include <stdio.h>
 
Index: clang-tools-extra/test/clang-tidy/checkers/google/readability-casting.c
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/google/readability-casting.c
+++ clang-tools-extra/test/clang-tidy/checkers/google/readability-casting.c
@@ -8,7 +8,7 @@
 #ifdef TEST_INCLUDE
 
 #undef TEST_INCLUDE
-#include "google-readability-casting.c"
+#include "readability-casting.c"
 
 #else
 
Index: clang-tools-extra/test/clang-tidy/checkers/hicpp/signed-bitwise-standard-types.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/hicpp/signed-bitwise-standard-types.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/hicpp/signed-bitwise-standard-types.cpp
@@ -1,7 +1,7 @@
 // RUN: clang-tidy %s -checks='-*,hicpp-signed-bitwise' -- -std=c++11
 // FIXME: Make the test work in all language modes.
 
-#include "hicpp-signed-bitwise-standard-types.h"
+#include "signed-bitwise-standard-types.h"
 
 void pure_bitmask_types() {
   // std::locale::category
Index: clang-tools-extra/test/clang-tidy/checkers/llvm/include-order.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/llvm/include-order.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/llvm/include-order.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s llvm-include-order %t -- -- -isystem %S/Inputs/Headers
+// RUN: %check_clang_tidy %s llvm-include-order %t -- -- -isystem %clang_tidy_headers
 
 // CHECK-MESSAGES: [[@LINE+2]]:1: warning: #includes are not sorted properly
 #include "j.h"
Index: clang-tools-extra/test/clang-tidy/checkers/llvmlibc/restrict-system-libc-headers.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/llvmlibc/restrict-system-libc-headers.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/llvmlibc/restrict-system-libc-headers.cpp
@@ -1,6 +1,6 @@
 // RUN: %check_clang_tidy %s llvmlibc-restrict-system-libc-headers %t \
-// RUN:   -- -- -isystem %S/Inputs/llvmlibc/system \
-// RUN:   -resource-dir %S/Inputs/llvmlibc/resource
+// RUN:   -- -- -isystem %S/Inputs/system \
+// RUN:   -resource-dir %S/Inputs/resource
 
 #include <stdio.h>
 // CHECK-MESSAGES: :[[@LINE-1]]:1: warning: system include stdio.h not allowed
Index: clang-tools-extra/test/clang-tidy/checkers/misc/unconventional-assign-operator.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/misc/unconventional-assign-operator.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/misc/unconventional-assign-operator.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s misc-unconventional-assign-operator %t -- -- -isystem %S/Inputs/Headers -fno-delayed-template-parsing
+// RUN: %check_clang_tidy %s misc-unconventional-assign-operator %t -- -- -fno-delayed-template-parsing
 
 namespace std {
 template <typename T>
Index: clang-tools-extra/test/clang-tidy/checkers/misc/unused-using-decls-cxx17.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/misc/unused-using-decls-cxx17.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/misc/unused-using-decls-cxx17.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy -std=c++17-or-later %s misc-unused-using-decls %t -- --fix-notes -- -fno-delayed-template-parsing -isystem %S/Inputs/
+// RUN: %check_clang_tidy -std=c++17-or-later %s misc-unused-using-decls %t -- --fix-notes -- -fno-delayed-template-parsing
 
 namespace ns {
 
Index: clang-tools-extra/test/clang-tidy/checkers/misc/unused-using-decls.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/misc/unused-using-decls.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/misc/unused-using-decls.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s misc-unused-using-decls %t -- --fix-notes -- -fno-delayed-template-parsing -isystem %S/Inputs/
+// RUN: %check_clang_tidy %s misc-unused-using-decls %t -- --fix-notes -- -fno-delayed-template-parsing -isystem %S/Inputs
 
 // ----- Definitions -----
 template <typename T> class vector {};
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/concat-nested-namespaces.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/concat-nested-namespaces.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/concat-nested-namespaces.cpp
@@ -1,10 +1,10 @@
-// RUN: cp %S/Inputs/modernize-concat-nested-namespaces/modernize-concat-nested-namespaces.h %T/modernize-concat-nested-namespaces.h
+// RUN: cp %S/Inputs/concat-nested-namespaces/modernize-concat-nested-namespaces.h %T/modernize-concat-nested-namespaces.h
 // RUN: %check_clang_tidy -std=c++17 %s modernize-concat-nested-namespaces %t -- -header-filter=".*" -- -I %T
-// RUN: FileCheck -input-file=%T/modernize-concat-nested-namespaces.h %S/Inputs/modernize-concat-nested-namespaces/modernize-concat-nested-namespaces.h -check-prefix=CHECK-FIXES
+// RUN: FileCheck -input-file=%T/modernize-concat-nested-namespaces.h %S/Inputs/concat-nested-namespaces/modernize-concat-nested-namespaces.h -check-prefix=CHECK-FIXES
 // Restore header file and re-run with c++20:
-// RUN: cp %S/Inputs/modernize-concat-nested-namespaces/modernize-concat-nested-namespaces.h %T/modernize-concat-nested-namespaces.h
+// RUN: cp %S/Inputs/concat-nested-namespaces/modernize-concat-nested-namespaces.h %T/modernize-concat-nested-namespaces.h
 // RUN: %check_clang_tidy -std=c++20 %s modernize-concat-nested-namespaces %t -- -header-filter=".*" -- -I %T
-// RUN: FileCheck -input-file=%T/modernize-concat-nested-namespaces.h %S/Inputs/modernize-concat-nested-namespaces/modernize-concat-nested-namespaces.h -check-prefix=CHECK-FIXES
+// RUN: FileCheck -input-file=%T/modernize-concat-nested-namespaces.h %S/Inputs/concat-nested-namespaces/modernize-concat-nested-namespaces.h -check-prefix=CHECK-FIXES
 
 #include "modernize-concat-nested-namespaces.h"
 // CHECK-MESSAGES-DAG: modernize-concat-nested-namespaces.h:1:1: warning: nested namespaces can be concatenated [modernize-concat-nested-namespaces]
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/deprecated-headers-cxx03.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/deprecated-headers-cxx03.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/deprecated-headers-cxx03.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy -std=c++98 %s modernize-deprecated-headers %t -- -extra-arg-before=-isystem%S/Inputs/modernize-deprecated-headers
+// RUN: %check_clang_tidy -std=c++98 %s modernize-deprecated-headers %t -- -extra-arg-before=-isystem%S/Inputs/deprecated-headers
 
 #include <assert.h>
 // CHECK-MESSAGES: :[[@LINE-1]]:10: warning: inclusion of deprecated C++ header 'assert.h'; consider using 'cassert' instead [modernize-deprecated-headers]
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/deprecated-headers-cxx11.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/deprecated-headers-cxx11.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/deprecated-headers-cxx11.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy -std=c++11-or-later %s modernize-deprecated-headers %t -- -extra-arg-before=-isystem%S/Inputs/modernize-deprecated-headers
+// RUN: %check_clang_tidy -std=c++11-or-later %s modernize-deprecated-headers %t -- -extra-arg-before=-isystem%S/Inputs/deprecated-headers
 
 #include <assert.h>
 // CHECK-MESSAGES: :[[@LINE-1]]:10: warning: inclusion of deprecated C++ header 'assert.h'; consider using 'cassert' instead [modernize-deprecated-headers]
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/deprecated-headers-extern-c.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/deprecated-headers-extern-c.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/deprecated-headers-extern-c.cpp
@@ -4,19 +4,19 @@
 // absolute file paths which is sorted by clang-tidy prior emitting.
 //
 // RUN: mkdir -p %t/sys && mkdir -p %t/usr \
-// RUN:   && cp %S/Inputs/modernize-deprecated-headers/mysystemlib.h %t/sys/mysystemlib.h \
-// RUN:   && cp %S/Inputs/modernize-deprecated-headers/mylib.h       %t/usr/mylib.h
+// RUN:   && cp %S/Inputs/deprecated-headers/mysystemlib.h %t/sys/mysystemlib.h \
+// RUN:   && cp %S/Inputs/deprecated-headers/mylib.h       %t/usr/mylib.h
 
 // RUN: %check_clang_tidy -std=c++11 %s modernize-deprecated-headers %t \
 // RUN:   -check-suffixes=DEFAULT \
 // RUN:   --header-filter='.*' --system-headers \
-// RUN:   -- -I %t/usr -isystem %t/sys -isystem %S/Inputs/modernize-deprecated-headers
+// RUN:   -- -I %t/usr -isystem %t/sys -isystem %S/Inputs/deprecated-headers
 
 // RUN: %check_clang_tidy -std=c++11 %s modernize-deprecated-headers %t \
 // RUN:   -check-suffixes=DEFAULT,CHECK-HEADER-FILE \
 // RUN:   -config="{CheckOptions: [{key: modernize-deprecated-headers.CheckHeaderFile, value: 'true'}]}" \
 // RUN:   --header-filter='.*' --system-headers \
-// RUN:   -- -I %t/usr -isystem %t/sys -isystem %S/Inputs/modernize-deprecated-headers
+// RUN:   -- -I %t/usr -isystem %t/sys -isystem %S/Inputs/deprecated-headers
 
 // REQUIRES: system-linux
 
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-basic.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-basic.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-basic.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s modernize-loop-convert %t -- -- -I %S/Inputs/modernize-loop-convert
+// RUN: %check_clang_tidy %s modernize-loop-convert %t -- -- -I %S/Inputs/loop-convert
 
 #include "structures.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-camelback.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-camelback.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-camelback.cpp
@@ -1,6 +1,6 @@
 // RUN: %check_clang_tidy %s modernize-loop-convert %t -- \
 // RUN:   -config="{CheckOptions: [{key: modernize-loop-convert.NamingStyle, value: 'camelBack'}]}" \
-// RUN:   -- -I %S/Inputs/modernize-loop-convert
+// RUN:   -- -I %S/Inputs/loop-convert
 
 #include "structures.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-extra.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-extra.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-extra.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s modernize-loop-convert %t -- -- -I %S/Inputs/modernize-loop-convert
+// RUN: %check_clang_tidy %s modernize-loop-convert %t -- -- -I %S/Inputs/loop-convert
 
 #include "structures.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-lowercase.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-lowercase.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-lowercase.cpp
@@ -1,6 +1,6 @@
 // RUN: %check_clang_tidy %s modernize-loop-convert %t -- \
 // RUN:   -config="{CheckOptions: [{key: modernize-loop-convert.NamingStyle, value: 'lower_case'}]}" \
-// RUN:   -- -I %S/Inputs/modernize-loop-convert
+// RUN:   -- -I %S/Inputs/loop-convert
 
 #include "structures.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-negative.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-negative.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-negative.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s modernize-loop-convert %t -- -- -I %S/Inputs/modernize-loop-convert
+// RUN: %check_clang_tidy %s modernize-loop-convert %t -- -- -I %S/Inputs/loop-convert
 
 #include "structures.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-rewritten-binop.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-rewritten-binop.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-rewritten-binop.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy -std=c++20 %s modernize-loop-convert %t -- -- -I %S/Inputs/modernize-loop-convert
+// RUN: %check_clang_tidy -std=c++20 %s modernize-loop-convert %t -- -- -I %S/Inputs/loop-convert
 
 namespace std {
 struct strong_ordering {
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-uppercase.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-uppercase.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/loop-convert-uppercase.cpp
@@ -1,6 +1,6 @@
 // RUN: %check_clang_tidy %s modernize-loop-convert %t -- \
 // RUN:   -config="{CheckOptions: [{key: modernize-loop-convert.NamingStyle, value: 'UPPER_CASE'}]}" \
-// RUN:   -- -I %S/Inputs/modernize-loop-convert
+// RUN:   -- -I %S/Inputs/loop-convert
 
 #include "structures.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/macro-to-enum.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/macro-to-enum.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/macro-to-enum.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy -std=c++14-or-later %s modernize-macro-to-enum %t -- -- -I%S/Inputs/modernize-macro-to-enum -fno-delayed-template-parsing
+// RUN: %check_clang_tidy -std=c++14-or-later %s modernize-macro-to-enum %t -- -- -I%S/Inputs/macro-to-enum -fno-delayed-template-parsing
 // C++14 or later required for binary literals.
 
 #if 1
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/make-shared-header.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/make-shared-header.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/make-shared-header.cpp
@@ -5,7 +5,7 @@
 // RUN:      {key: modernize-make-shared.MakeSmartPtrFunctionHeader, \
 // RUN:       value: 'make_shared_util.h'} \
 // RUN:     ]}" \
-// RUN:   -- -I %S/Inputs/modernize-smart-ptr
+// RUN:   -- -I %S/Inputs/smart-ptr
 
 #include "shared_ptr.h"
 // CHECK-FIXES: #include "make_shared_util.h"
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/make-shared.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/make-shared.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/make-shared.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s modernize-make-shared %t -- -- -I %S/Inputs/modernize-smart-ptr
+// RUN: %check_clang_tidy %s modernize-make-shared %t -- -- -I %S/Inputs/smart-ptr
 
 #include "shared_ptr.h"
 // CHECK-FIXES: #include <memory>
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique-cxx11.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique-cxx11.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique-cxx11.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy -std=c++11 %s modernize-make-unique %t -- -- -I %S/Inputs/modernize-smart-ptr
+// RUN: %check_clang_tidy -std=c++11 %s modernize-make-unique %t -- -- -I %S/Inputs/smart-ptr
 
 #include "unique_ptr.h"
 // CHECK-FIXES: #include "unique_ptr.h"
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique-default-init.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique-default-init.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique-default-init.cpp
@@ -3,7 +3,7 @@
 // RUN:             [{key: modernize-make-unique.IgnoreDefaultInitialization, \
 // RUN:               value: 'false'}] \
 // RUN:             }" \
-// RUN:   -- -I %S/Inputs/modernize-smart-ptr
+// RUN:   -- -I %S/Inputs/smart-ptr
 
 #include "initializer_list.h"
 #include "unique_ptr.h"
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique-header.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique-header.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique-header.cpp
@@ -5,7 +5,7 @@
 // RUN:      {key: modernize-make-unique.MakeSmartPtrFunctionHeader, \
 // RUN:       value: 'make_unique_util.h'} \
 // RUN:     ]}" \
-// RUN:   -- -I %S/Inputs/modernize-smart-ptr
+// RUN:   -- -I %S/Inputs/smart-ptr
 
 #include "unique_ptr.h"
 // CHECK-FIXES: #include "make_unique_util.h"
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique-inaccessible-ctors.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique-inaccessible-ctors.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique-inaccessible-ctors.cpp
@@ -1,5 +1,5 @@
-// RUN: %check_clang_tidy -std=c++14,c++17 -check-suffix=CXX-14-17 %s modernize-make-unique %t -- -- -I %S/Inputs/modernize-smart-ptr -D CXX_14_17=1
-// RUN: %check_clang_tidy -std=c++20 -check-suffix=CXX-20 %s modernize-make-unique %t -- -- -I %S/Inputs/modernize-smart-ptr -D CXX_20=1
+// RUN: %check_clang_tidy -std=c++14,c++17 -check-suffix=CXX-14-17 %s modernize-make-unique %t -- -- -I %S/Inputs/smart-ptr -D CXX_14_17=1
+// RUN: %check_clang_tidy -std=c++20 -check-suffix=CXX-20 %s modernize-make-unique %t -- -- -I %S/Inputs/smart-ptr -D CXX_20=1
 
 #include "unique_ptr.h"
 // CHECK-FIXES: #include <memory>
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique-macros.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique-macros.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique-macros.cpp
@@ -1,6 +1,6 @@
 // RUN: %check_clang_tidy -std=c++14-or-later %s modernize-make-unique %t -- \
 // RUN:   -config="{CheckOptions: [{key: modernize-make-unique.IgnoreMacros, value: false}]}" \
-// RUN:   -- -I %S/Inputs/modernize-smart-ptr
+// RUN:   -- -I %S/Inputs/smart-ptr
 
 #include "unique_ptr.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy -std=c++14-or-later %s modernize-make-unique %t -- -- -I %S/Inputs/modernize-smart-ptr
+// RUN: %check_clang_tidy -std=c++14-or-later %s modernize-make-unique %t -- -- -I %S/Inputs/smart-ptr
 
 #include "unique_ptr.h"
 #include "initializer_list.h"
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/pass-by-value-header.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/pass-by-value-header.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/pass-by-value-header.cpp
@@ -1,4 +1,4 @@
-// RUN: cp %S/Inputs/modernize-pass-by-value/header.h %T/pass-by-value-header.h
+// RUN: cp %S/Inputs/pass-by-value/header.h %T/pass-by-value-header.h
 // RUN: clang-tidy %s -checks='-*,modernize-pass-by-value' -header-filter='.*' -fix -- -std=c++11 -I %T | FileCheck %s -check-prefix=CHECK-MESSAGES -implicit-check-not="{{warning|error}}:"
 // RUN: FileCheck -input-file=%T/pass-by-value-header.h %s -check-prefix=CHECK-FIXES
 // FIXME: Make the test work in all language modes.
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/pass-by-value-macro-header.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/pass-by-value-macro-header.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/pass-by-value-macro-header.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s modernize-pass-by-value %t -- -- -isystem %S/Inputs/Headers
+// RUN: %check_clang_tidy %s modernize-pass-by-value %t -- -- -isystem %clang_tidy_headers
 
 // CHECK-FIXES: #include <utility>
 
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/pass-by-value-multi-fixes.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/pass-by-value-multi-fixes.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/pass-by-value-multi-fixes.cpp
@@ -1,4 +1,4 @@
-// RUN: cat %S/Inputs/modernize-pass-by-value/header-with-fix.h > %T/pass-by-value-header-with-fix.h
+// RUN: cat %S/Inputs/pass-by-value/header-with-fix.h > %T/pass-by-value-header-with-fix.h
 // RUN: sed -e 's#//.*$##' %s > %t.cpp
 // RUN: clang-tidy %t.cpp -checks='-*,modernize-pass-by-value' -header-filter='.*' -fix -- -std=c++11 -I %T | FileCheck %s -check-prefix=CHECK-MESSAGES -implicit-check-not="{{warning|error}}:"
 // RUN: FileCheck -input-file=%t.cpp %s -check-prefix=CHECK-FIXES
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/replace-auto-ptr.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/replace-auto-ptr.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/replace-auto-ptr.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s modernize-replace-auto-ptr %t -- -- -I %S/Inputs/modernize-replace-auto-ptr
+// RUN: %check_clang_tidy %s modernize-replace-auto-ptr %t -- -- -I %S/Inputs/replace-auto-ptr
 
 // CHECK-FIXES: #include <utility>
 
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/use-auto-cast.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/use-auto-cast.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/use-auto-cast.cpp
@@ -1,6 +1,6 @@
 // RUN: %check_clang_tidy %s modernize-use-auto %t -- \
 // RUN:   -config="{CheckOptions: [{key: modernize-use-auto.MinTypeNameLength, value: '0'}]}" \
-// RUN:   -- -I %S/Inputs/modernize-use-auto -frtti
+// RUN:   -- -I %S/Inputs/use-auto -frtti
 
 struct A {
   virtual ~A() {}
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/use-auto-iterator.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/use-auto-iterator.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/use-auto-iterator.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy -std=c++11,c++14 %s modernize-use-auto %t -- -- -I %S/Inputs/modernize-use-auto
+// RUN: %check_clang_tidy -std=c++11,c++14 %s modernize-use-auto %t -- -- -I %S/Inputs/use-auto
 // FIXME: Fix the checker to work in C++17 mode.
 
 #include "containers.h"
Index: clang-tools-extra/test/clang-tidy/checkers/modernize/use-using.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/modernize/use-using.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/modernize/use-using.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s modernize-use-using %t -- -- -I %S/Inputs/modernize-use-using/
+// RUN: %check_clang_tidy %s modernize-use-using %t -- -- -I %S/Inputs/use-using/
 
 typedef int Type;
 // CHECK-MESSAGES: :[[@LINE-1]]:1: warning: use 'using' instead of 'typedef' [modernize-use-using]
Index: clang-tools-extra/test/clang-tidy/checkers/mpi/buffer-deref.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/mpi/buffer-deref.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/mpi/buffer-deref.cpp
@@ -1,5 +1,5 @@
 // REQUIRES: static-analyzer
-// RUN: %check_clang_tidy %s mpi-buffer-deref %t -- -- -I %S/Inputs/mpi-type-mismatch
+// RUN: %check_clang_tidy %s mpi-buffer-deref %t -- -- -I %S/Inputs/type-mismatch
 
 #include "mpimock.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/mpi/type-mismatch.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/mpi/type-mismatch.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/mpi/type-mismatch.cpp
@@ -1,5 +1,5 @@
 // REQUIRES: static-analyzer
-// RUN: %check_clang_tidy %s mpi-type-mismatch %t -- -- -I %S/Inputs/mpi-type-mismatch
+// RUN: %check_clang_tidy %s mpi-type-mismatch %t -- -- -I %S/Inputs/type-mismatch
 
 #include "mpimock.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/objc/assert-equals.m
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/objc/assert-equals.m
+++ clang-tools-extra/test/clang-tidy/checkers/objc/assert-equals.m
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s objc-assert-equals %t -- -- -I %S/Inputs/objc-assert
+// RUN: %check_clang_tidy %s objc-assert-equals %t -- -- -I %S/Inputs/assert
 #include "XCTestAssertions.h"
 // Can't reference NSString directly so we use this getStr() instead.
 __typeof(@"abc") getStr(void) {
Index: clang-tools-extra/test/clang-tidy/checkers/performance/move-constructor-init.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/performance/move-constructor-init.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/performance/move-constructor-init.cpp
@@ -1,7 +1,7 @@
 // RUN: %check_clang_tidy %s performance-move-constructor-init,modernize-pass-by-value %t -- \
 // RUN: -config='{CheckOptions: \
 // RUN:  [{key: modernize-pass-by-value.ValuesOnly, value: true}]}' \
-// RUN: -- -isystem %S/Inputs/Headers
+// RUN: -- -isystem %clang_tidy_headers
 
 #include <s.h>
 
Index: clang-tools-extra/test/clang-tidy/checkers/performance/unnecessary-value-param-header.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/performance/unnecessary-value-param-header.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/performance/unnecessary-value-param-header.cpp
@@ -1,8 +1,8 @@
 // RUN: rm -rf %t
 // RUN: mkdir %t
-// RUN: cp %S/Inputs/performance-unnecessary-value-param/header.h %t/header.h
+// RUN: cp %S/Inputs/unnecessary-value-param/header.h %t/header.h
 // RUN: %check_clang_tidy %s performance-unnecessary-value-param %t/temp -- -- -I %t
-// RUN: diff %t/header.h %S/Inputs/performance-unnecessary-value-param/header-fixed.h
+// RUN: diff %t/header.h %S/Inputs/unnecessary-value-param/header-fixed.h
 
 #include "header.h"
 
Index: clang-tools-extra/test/clang-tidy/checkers/portability/restrict-system-includes-allow.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/portability/restrict-system-includes-allow.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/portability/restrict-system-includes-allow.cpp
@@ -1,6 +1,6 @@
 // RUN: %check_clang_tidy %s portability-restrict-system-includes %t \
 // RUN:     -- -config="{CheckOptions: [{key: portability-restrict-system-includes.Includes, value: '*,-stddef.h'}]}" \
-// RUN:     -- -isystem %S/Inputs/portability-restrict-system-includes/system
+// RUN:     -- -isystem %S/Inputs/restrict-system-includes/system
 
 // Test block-list functionality: allow all but stddef.h.
 
Index: clang-tools-extra/test/clang-tidy/checkers/portability/restrict-system-includes-disallow.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/portability/restrict-system-includes-disallow.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/portability/restrict-system-includes-disallow.cpp
@@ -1,6 +1,6 @@
 // RUN: %check_clang_tidy %s portability-restrict-system-includes %t \
 // RUN:     -- -config="{CheckOptions: [{key: portability-restrict-system-includes.Includes, value: '-*,stddef.h'}]}" \
-// RUN:     -- -isystem %S/Inputs/portability-restrict-system-includes/system
+// RUN:     -- -isystem %S/Inputs/restrict-system-includes/system
 
 // Test allow-list functionality: disallow all but stddef.h.
 
Index: clang-tools-extra/test/clang-tidy/checkers/portability/restrict-system-includes-glob.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/portability/restrict-system-includes-glob.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/portability/restrict-system-includes-glob.cpp
@@ -1,6 +1,6 @@
 // RUN: %check_clang_tidy %s portability-restrict-system-includes %t \
 // RUN:     -- -config="{CheckOptions: [{key: portability-restrict-system-includes.Includes, value: '-*,std*.h'}]}" \
-// RUN:     -- -isystem %S/Inputs/portability-restrict-system-includes/system
+// RUN:     -- -isystem %S/Inputs/restrict-system-includes/system
 
 // Test glob functionality: disallow all headers except those that match
 // pattern "std*.h".
Index: clang-tools-extra/test/clang-tidy/checkers/portability/restrict-system-includes-transitive.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/portability/restrict-system-includes-transitive.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/portability/restrict-system-includes-transitive.cpp
@@ -1,6 +1,6 @@
 // RUN: rm -rf %T/Headers
 // RUN: mkdir %T/Headers
-// RUN: cp -r %S/Inputs/portability-restrict-system-includes %T/Headers/portability-restrict-system-includes
+// RUN: cp -r %S/Inputs/restrict-system-includes %T/Headers/portability-restrict-system-includes
 // RUN: %check_clang_tidy -std=c++11 %s portability-restrict-system-includes %t \
 // RUN:   -- -config="{CheckOptions: [{key: portability-restrict-system-includes.Includes, value: 'transitive.h,s.h'}]}" \
 // RUN:   -system-headers -header-filter=.* \
Index: clang-tools-extra/test/clang-tidy/checkers/readability/Inputs/duplicate-include/duplicate-include.h
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/readability/Inputs/duplicate-include/duplicate-include.h
+++ clang-tools-extra/test/clang-tidy/checkers/readability/Inputs/duplicate-include/duplicate-include.h
@@ -2,13 +2,13 @@
 #define READABILITY_DUPLICATE_INCLUDE_H
 
 extern int g;
-#include "readability-duplicate-include2.h"
+#include "duplicate-include2.h"
 extern int h;
-#include "readability-duplicate-include2.h"
+#include "duplicate-include2.h"
 extern int i;
 // CHECK-MESSAGES: :[[@LINE-2]]:1: warning: duplicate include
 // CHECK-FIXES:      {{^extern int g;$}}
-// CHECK-FIXES-NEXT: {{^#include "readability-duplicate-include2.h"$}}
+// CHECK-FIXES-NEXT: {{^#include "duplicate-include2.h"$}}
 // CHECK-FIXES-NEXT: {{^extern int h;$}}
 // CHECK-FIXES-NEXT: {{^extern int i;$}}
 
Index: clang-tools-extra/test/clang-tidy/checkers/readability/duplicate-include.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/readability/duplicate-include.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/readability/duplicate-include.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s readability-duplicate-include %t -- -- -isystem %S/Inputs/readability-duplicate-include/system -I %S/Inputs/readability-duplicate-include
+// RUN: %check_clang_tidy %s readability-duplicate-include %t -- -- -isystem %S/Inputs/duplicate-include/system -I %S/Inputs/duplicate-include
 
 int a;
 #include <string.h>
@@ -23,13 +23,13 @@
 // CHECK-FIXES-NEXT: {{^int f;$}}
 
 int g;
-#include "readability-duplicate-include.h"
+#include "duplicate-include.h"
 int h;
-#include "readability-duplicate-include.h"
+#include "duplicate-include.h"
 int i;
 // CHECK-MESSAGES: :[[@LINE-2]]:1: warning: duplicate include
 // CHECK-FIXES:      {{^int g;$}}
-// CHECK-FIXES-NEXT: {{^#include "readability-duplicate-include.h"$}}
+// CHECK-FIXES-NEXT: {{^#include "duplicate-include.h"$}}
 // CHECK-FIXES-NEXT: {{^int h;$}}
 // CHECK-FIXES-NEXT: {{^int i;$}}
 
Index: clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming-hungarian-notation-cfgfile.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming-hungarian-notation-cfgfile.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming-hungarian-notation-cfgfile.cpp
@@ -1,4 +1,4 @@
-// RUN: clang-tidy %s --config-file=%S/Inputs/readability-identifier-naming/hungarian-notation1/.clang-tidy 2>&1 \
+// RUN: clang-tidy %s --config-file=%S/Inputs/identifier-naming/hungarian-notation1/.clang-tidy 2>&1 \
 // RUN:   | FileCheck -check-prefixes=CHECK-MESSAGES %s
 
 // clang-format off
Index: clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming-hungarian-notation.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming-hungarian-notation.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming-hungarian-notation.cpp
@@ -1,4 +1,4 @@
-// RUN: clang-tidy %s --config-file=%S/Inputs/readability-identifier-naming/hungarian-notation2/.clang-tidy 2>&1 \
+// RUN: clang-tidy %s --config-file=%S/Inputs/identifier-naming/hungarian-notation2/.clang-tidy 2>&1 \
 // RUN:   | FileCheck -check-prefixes=CHECK-MESSAGES %s
 
 // clang-format off
Index: clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming-multiple-styles.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming-multiple-styles.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming-multiple-styles.cpp
@@ -2,7 +2,7 @@
 
 // RUN: rm -rf %theaders
 // RUN: mkdir %theaders
-// RUN: cp -R %S/Inputs/readability-identifier-naming/. %theaders
+// RUN: cp -R %S/Inputs/identifier-naming/. %theaders
 
 // C++11 isn't explicitly required, but failing to specify a standard means the
 // check will run multiple times for different standards. This will cause the
@@ -19,7 +19,7 @@
 
 // On DISABLED run, everything should be made 'camelBack'.
 
-// RUN: cp -R %S/Inputs/readability-identifier-naming/. %theaders
+// RUN: cp -R %S/Inputs/identifier-naming/. %theaders
 // RUN: %check_clang_tidy -check-suffixes=DISABLED,SHARED -std=c++11 %s \
 // RUN: readability-identifier-naming %t -- \
 // RUN:  -config='{ InheritParentConfig: false, CheckOptions: [ \
Index: clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming.cpp
@@ -82,8 +82,8 @@
 // RUN:     {key: readability-identifier-naming.LocalConstantPointerCase, value: CamelCase}, \
 // RUN:     {key: readability-identifier-naming.LocalConstantPointerPrefix, value: 'lc_'}, \
 // RUN:   ]}' -- -fno-delayed-template-parsing -Dbad_macro -std=c++17 -fcoroutines-ts \
-// RUN:   -I%S/Inputs/readability-identifier-naming \
-// RUN:   -isystem %S/Inputs/readability-identifier-naming/system
+// RUN:   -I%S/Inputs/identifier-naming \
+// RUN:   -isystem %S/Inputs/identifier-naming/system
 
 // clang-format off
 
Index: clang-tools-extra/test/clang-tidy/checkers/readability/redundant-preprocessor.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/readability/redundant-preprocessor.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/readability/redundant-preprocessor.cpp
@@ -19,7 +19,7 @@
 #endif
 
 // Negative testing.
-#include "readability-redundant-preprocessor.h"
+#include "redundant-preprocessor.h"
 
 #ifndef BAR
 void g();
Index: clang-tools-extra/test/clang-tidy/checkers/readability/static-accessed-through-instance.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/readability/static-accessed-through-instance.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/readability/static-accessed-through-instance.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s readability-static-accessed-through-instance %t -- -- -isystem %S/Inputs/readability-static-accessed-through-instance
+// RUN: %check_clang_tidy %s readability-static-accessed-through-instance %t -- -- -isystem %S/Inputs/static-accessed-through-instance
 #include <__clang_cuda_builtin_vars.h>
 
 struct C {
Index: clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-float16.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-float16.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-float16.cpp
@@ -1,6 +1,6 @@
 // RUN: %check_clang_tidy %s readability-uppercase-literal-suffix %t -- -- -target aarch64-linux-gnu -I %S
 
-#include "readability-uppercase-literal-suffix.h"
+#include "uppercase-literal-suffix.h"
 
 void float16_normal_literals() {
   // _Float16
Index: clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-floating-point.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-floating-point.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-floating-point.cpp
@@ -3,7 +3,7 @@
 // RUN: clang-tidy %t.cpp -checks='-*,readability-uppercase-literal-suffix' -fix -- -target x86_64-pc-linux-gnu -I %S
 // RUN: clang-tidy %t.cpp -checks='-*,readability-uppercase-literal-suffix' -warnings-as-errors='-*,readability-uppercase-literal-suffix' -- -target x86_64-pc-linux-gnu -I %S
 
-#include "readability-uppercase-literal-suffix.h"
+#include "uppercase-literal-suffix.h"
 
 void floating_point_suffix() {
   static constexpr auto v0 = 1.; // no literal
Index: clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-hexadecimal-floating-point.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-hexadecimal-floating-point.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-hexadecimal-floating-point.cpp
@@ -3,7 +3,7 @@
 // RUN: clang-tidy %t.cpp -checks='-*,readability-uppercase-literal-suffix' -fix -- -target x86_64-pc-linux-gnu -I %S
 // RUN: clang-tidy %t.cpp -checks='-*,readability-uppercase-literal-suffix' -warnings-as-errors='-*,readability-uppercase-literal-suffix' -- -target x86_64-pc-linux-gnu -I %S
 
-#include "readability-uppercase-literal-suffix.h"
+#include "uppercase-literal-suffix.h"
 
 void floating_point_suffix() {
   static constexpr auto v0 = 0x0p0; // no literal
Index: clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-integer-custom-list.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-integer-custom-list.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-integer-custom-list.cpp
@@ -3,7 +3,7 @@
 // RUN: clang-tidy %t.cpp -checks='-*,readability-uppercase-literal-suffix' -fix -config="{CheckOptions: [{key: readability-uppercase-literal-suffix.NewSuffixes, value: 'L;uL'}]}" -- -I %S
 // RUN: clang-tidy %t.cpp -checks='-*,readability-uppercase-literal-suffix' -warnings-as-errors='-*,readability-uppercase-literal-suffix' -config="{CheckOptions: [{key: readability-uppercase-literal-suffix.NewSuffixes, value: 'L;uL'}]}" -- -I %S
 
-#include "readability-uppercase-literal-suffix.h"
+#include "uppercase-literal-suffix.h"
 
 void integer_suffix() {
   // Unsigned
Index: clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-integer-ms.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-integer-ms.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-integer-ms.cpp
@@ -3,7 +3,7 @@
 // RUN: clang-tidy %t.cpp -checks='-*,readability-uppercase-literal-suffix' -fix -- -target x86_64-pc-linux-gnu -I %S -fms-extensions
 // RUN: clang-tidy %t.cpp -checks='-*,readability-uppercase-literal-suffix' -warnings-as-errors='-*,readability-uppercase-literal-suffix' -- -target x86_64-pc-linux-gnu -I %S -fms-extensions
 
-#include "readability-uppercase-literal-suffix.h"
+#include "uppercase-literal-suffix.h"
 
 void integer_suffix() {
   static constexpr auto v0 = __LINE__; // synthetic
Index: clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-integer.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-integer.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/readability/uppercase-literal-suffix-integer.cpp
@@ -3,7 +3,7 @@
 // RUN: clang-tidy %t.cpp -checks='-*,readability-uppercase-literal-suffix' -fix -- -I %S
 // RUN: clang-tidy %t.cpp -checks='-*,readability-uppercase-literal-suffix' -warnings-as-errors='-*,readability-uppercase-literal-suffix' -- -I %S
 
-#include "readability-uppercase-literal-suffix.h"
+#include "uppercase-literal-suffix.h"
 
 void integer_suffix() {
   static constexpr auto v0 = __LINE__; // synthetic
Index: clang-tools-extra/test/lit.cfg.py
===================================================================
--- clang-tools-extra/test/lit.cfg.py
+++ clang-tools-extra/test/lit.cfg.py
@@ -51,6 +51,10 @@
 config.substitutions.append(
     ('%run_clang_tidy',
      '%s %s' % (python_exec, run_clang_tidy)) )
+clang_tidy_headers = os.path.join(
+    config.test_source_root, "clang-tidy", "checkers", "Inputs", "Headers")
+config.substitutions.append(
+    ("%clang_tidy_headers", clang_tidy_headers) )
 
 # Plugins (loadable modules)
 if config.has_plugins and config.llvm_plugin_ext: