[clang-tidy][doc] Improve clang-tidy documentation

[carlosgalvezp]

Summary

• Specify that the .clang-tidy file is in YAML format.
• Document the options that may be used in the .clang-tidy file,
• Add missing documentation for existing options (User).
• Fix spurious newline after the dash that comes after every command-line option. This was inconsistent with single-line descriptions, which lacked a newline. The description is now aligned with the dash and the corresponding command-line option, more visually pleasing.

This enables documenting upcoming global clang-tidy
configuration options.

[carlosgalvezp]

Remove extra newline

[carlosgalvezp]

Remove wrong dash in key/value options.

[carlosgalvezp]

Fix incorrect dash in key/value pairs

[carlosgalvezp]

Remove colon after the config options, for consistency with
the command-line options.

[carlosgalvezp]

Fix alignment

[Eugene.Zelenko]

clang-tools-extra/docs/clang-tidy/index.rst

143

Is this merge artifact? Same below.

220

Ditto.

[carlosgalvezp]

clang-tools-extra/docs/clang-tidy/index.rst

143

I honestly have no idea, it seems some artifact of Phabricator that is unrelated to the code which is just fine. It's not a tab either, checked with my editor. I have seen it in patches from other people as well, leading to confusion...

[Eugene.Zelenko]

But will be good idea to wait for other reviewers.

[carlosgalvezp]

Fix formatting

[carlosgalvezp]

Trim first character instead, to keep the code visually
pleasing.

[carlosgalvezp]

@njames93 Do you agree with the overall idea of documenting config file options like this? I need this in place for the other patch that cleans the duplication for HeaderFileExtensions, ImplementationFileExtensions, IncludeStyle, etc.

[njames93]

clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp

34

This seems a bit of a needless change, if you want to remove the newline, just in date the raw string literal and remove the empty line

53

Can this be changed to match the previous format defined below

91

This change can be reverted.

clang-tools-extra/docs/clang-tidy/index.rst

262

Again as before

302

Ditto

[carlosgalvezp]

Revert changes to CheckOptions

clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp

34

I'm not sure I understand what you mean by "just in date the raw string", could you clarify?

In Diff 7 I fixed this without TrimFirstChar, but it leads to fairly inconsistent code, where the first R"( needs to be part of the first line of text:

R"(some text
some more text
)"

versus:

R"(
some text
some more text
)"

Let me know which option you prefer.

91

Thanks, I didn't know it was another valid way to write it! Will fix

[carlosgalvezp]

Add ExtraArgs and ExtraArgsBefore

[carlosgalvezp]

Add HeaderFileExtensions and ImplementationFileExtensions

[carlosgalvezp]

Fix formatting

[carlosgalvezp]

Remove newline

[carlosgalvezp]

Friendly ping @njames93 , see my previous comment about TrimFirstChar.

[PiotrZSL]

clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp

34

Looks like usecase of this is more like rtrim, then probably rtrim should be used instead of substr.
And probably better would be to replace entire cl::desc. instead of adding new additional wrap.

more like:
static auto desc(llvm::StringRef description) { return cl::desc(description.rtrim()); }

[carlosgalvezp]

Wrap trimming functionality in desc function.

[carlosgalvezp]

clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp

34

Really good idea, much better! Done.

[carlosgalvezp]

All comments have been addressed, I intend to land the patch by February 9th unless more feedback is received.

[PiotrZSL]

clang-tools-extra/docs/clang-tidy/index.rst

273

This is a bug, SystemHeaders cannot be specified on this level, as they not added to MappingTraits<ClangTidyOptions>. Therefor listing them here is a misleading.

clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp

 #include "llvm/Support/Signals.h"
 #include "llvm/Support/TargetSelect.h"
 #include "llvm/Support/WithColor.h"
 #include <optional>
 
 using namespace clang::tooling;
 using namespace llvm;
 
+static StringRef TrimFirstChar(StringRef x) { return x.substr(1); }
+
 static cl::OptionCategory ClangTidyCategory("clang-tidy options");
 
 static cl::extrahelp CommonHelp(CommonOptionsParser::HelpMessage);
 static cl::extrahelp ClangTidyHelp(R"(
 Configuration files:
   clang-tidy attempts to read configuration for each source file from a
   .clang-tidy file located in the closest parent directory of the source
-  file. If InheritParentConfig is true in a config file, the configuration file
-  in the parent directory (if any exists) will be taken and current config file
-  will be applied on top of the parent one. If any configuration options have
-  a corresponding command-line option, command-line option takes precedence.
-  The effective configuration can be inspected using -dump-config:
+  file. The .clang-tidy file is specified in YAML format. If any configuration
+  options have a corresponding command-line option, command-line option takes
+  precedence.
+
+  The following configuration options may be used in a .clang-tidy file:
+
+  CheckOptions                 - List of key-value pairs defining check-specific
+                                 options. Example:
+                                   CheckOptions:
+                                     some-check.SomeOption: 'some value'
+  Checks                       - Same as '--checks'.
+  ExtraArgs                    - Same as '--extra-args'.
+  ExtraArgsBefore              - Same as '--extra-args-before'.
+  FormatStyle                  - Same as '--format-style'.
+  HeaderFileExtensions         - File extensions to consider to determine if a
+                                 given diagnostic is located in a header file.
+                                 Default: ['','h','hh','hpp','hxx']
+  HeaderFilterRegex            - Same as '--header-filter-regex'.
+  ImplementationFileExtensions - File extensions to consider to determine if a
+                                 given diagnostic is located in an
+                                 implementation file.
+                                 Default: ['c','cc','cpp','cxx']
+  InheritParentConfig          - If this option is true in a config file, the
+                                 configuration file in the parent directory
+                                 (if any exists) will be taken and the current
+                                 config file will be applied on top of the
+                                 parent one.
+  SystemHeaders                - Same as '--system-headers'.
+  UseColor                     - Same as '--use-color'.
+  User                         - Specifies the name or e-mail of the user
+                                 running clang-tidy. This option is used, for
+                                 example, to place the correct user name in
+                                 TODO() comments in the relevant check.
+  WarningsAsErrors             - Same as '--warnings-as-errors'.
 
-    $ clang-tidy -dump-config
+  The effective configuration can be inspected using --dump-config:
+
+    $ clang-tidy --dump-config
     ---
     Checks:                       '-*,some-check'
     WarningsAsErrors:             ''
     HeaderFileExtensions:         ['', 'h','hh','hpp','hxx']
     ImplementationFileExtensions: ['c','cc','cpp','cxx']
     HeaderFilterRegex:            ''
     FormatStyle:                  none
     InheritParentConfig:          true
     User:                         user
     CheckOptions:
       some-check.SomeOption: 'some value'
     ...
 
 )");
 
 const char DefaultChecks[] = // Enable these checks by default:
     "clang-diagnostic-*,"    //   * compiler diagnostics
     "clang-analyzer-*";      //   * Static Analyzer checks
 
-static cl::opt<std::string> Checks("checks", cl::desc(R"(
+static cl::opt<std::string> Checks("checks", cl::desc(TrimFirstChar(R"(
 Comma-separated list of globs with optional '-'
 prefix. Globs are processed in order of
 appearance in the list. Globs without '-'
 prefix add checks with matching names to the
 set, globs with the '-' prefix remove checks
 with matching names from the set of enabled
 checks. This option's value is appended to the
 value of the 'Checks' option in .clang-tidy
 file, if any.
-)"),
+)")),
                                    cl::init(""), cl::cat(ClangTidyCategory));
 
-static cl::opt<std::string> WarningsAsErrors("warnings-as-errors", cl::desc(R"(
+static cl::opt<std::string> WarningsAsErrors("warnings-as-errors",
+                                             cl::desc(TrimFirstChar(R"(
 Upgrades warnings to errors. Same format as
 '-checks'.
 This option's value is appended to the value of
 the 'WarningsAsErrors' option in .clang-tidy
 file, if any.
-)"),
+)")),
                                              cl::init(""),
                                              cl::cat(ClangTidyCategory));
 
-static cl::opt<std::string> HeaderFilter("header-filter", cl::desc(R"(
+static cl::opt<std::string> HeaderFilter("header-filter",
+                                         cl::desc(TrimFirstChar(R"(
 Regular expression matching the names of the
 headers to output diagnostics from. Diagnostics
 from the main file of each translation unit are
 always displayed.
 Can be used together with -line-filter.
 This option overrides the 'HeaderFilterRegex'
 option in .clang-tidy file, if any.
-)"),
+)")),
                                          cl::init(""),
                                          cl::cat(ClangTidyCategory));
 
 static cl::opt<bool>
     SystemHeaders("system-headers",
                   cl::desc("Display the errors from system headers."),
                   cl::init(false), cl::cat(ClangTidyCategory));
-static cl::opt<std::string> LineFilter("line-filter", cl::desc(R"(
+static cl::opt<std::string> LineFilter("line-filter", cl::desc(TrimFirstChar(R"(
 List of files with line ranges to filter the
 warnings. Can be used together with
 -header-filter. The format of the list is a
 JSON array of objects:
   [
     {"name":"file1.cpp","lines":[[1,3],[5,7]]},
     {"name":"file2.h"}
   ]
-)"),
+)")),
                                        cl::init(""),
                                        cl::cat(ClangTidyCategory));
 
-static cl::opt<bool> Fix("fix", cl::desc(R"(
+static cl::opt<bool> Fix("fix", cl::desc(TrimFirstChar(R"(
 Apply suggested fixes. Without -fix-errors
 clang-tidy will bail out if any compilation
 errors were found.
-)"),
+)")),
                          cl::init(false), cl::cat(ClangTidyCategory));
 
-static cl::opt<bool> FixErrors("fix-errors", cl::desc(R"(
+static cl::opt<bool> FixErrors("fix-errors", cl::desc(TrimFirstChar(R"(
 Apply suggested fixes even if compilation
 errors were found. If compiler errors have
 attached fix-its, clang-tidy will apply them as
 well.
-)"),
+)")),
                                cl::init(false), cl::cat(ClangTidyCategory));
 
-static cl::opt<bool> FixNotes("fix-notes", cl::desc(R"(
+static cl::opt<bool> FixNotes("fix-notes", cl::desc(TrimFirstChar(R"(
 If a warning has no fix, but a single fix can
 be found through an associated diagnostic note,
 apply the fix.
 Specifying this flag will implicitly enable the
 '--fix' flag.
-)"),
+)")),
                               cl::init(false), cl::cat(ClangTidyCategory));
 
-static cl::opt<std::string> FormatStyle("format-style", cl::desc(R"(
+static cl::opt<std::string> FormatStyle("format-style",
+                                        cl::desc(TrimFirstChar(R"(
 Style for formatting code around applied fixes:
   - 'none' (default) turns off formatting
   - 'file' (literally 'file', not a placeholder)
     uses .clang-format file in the closest parent
     directory
   - '{ <json> }' specifies options inline, e.g.
     -format-style='{BasedOnStyle: llvm, IndentWidth: 8}'
   - 'llvm', 'google', 'webkit', 'mozilla'
 See clang-format documentation for the up-to-date
 information about formatting styles and options.
 This option overrides the 'FormatStyle` option in
 .clang-tidy file, if any.
-)"),
+)")),
                                         cl::init("none"),
                                         cl::cat(ClangTidyCategory));
 
-static cl::opt<bool> ListChecks("list-checks", cl::desc(R"(
+static cl::opt<bool> ListChecks("list-checks", cl::desc(TrimFirstChar(R"(
 List all enabled checks and exit. Use with
 -checks=* to list all available checks.
-)"),
+)")),
                                 cl::init(false), cl::cat(ClangTidyCategory));
 
-static cl::opt<bool> ExplainConfig("explain-config", cl::desc(R"(
+static cl::opt<bool> ExplainConfig("explain-config", cl::desc(TrimFirstChar(R"(
 For each enabled check explains, where it is
 enabled, i.e. in clang-tidy binary, command
 line or a specific configuration file.
-)"),
+)")),
                                    cl::init(false), cl::cat(ClangTidyCategory));
 
-static cl::opt<std::string> Config("config", cl::desc(R"(
+static cl::opt<std::string> Config("config", cl::desc(TrimFirstChar(R"(
 Specifies a configuration in YAML/JSON format:
   -config="{Checks: '*',
             CheckOptions: {x: y}}"
 When the value is empty, clang-tidy will
 attempt to find a file named .clang-tidy for
 each source file in its parent directories.
-)"),
+)")),
                                    cl::init(""), cl::cat(ClangTidyCategory));
 
-static cl::opt<std::string> ConfigFile("config-file", cl::desc(R"(
+static cl::opt<std::string> ConfigFile("config-file", cl::desc(TrimFirstChar(R"(
 Specify the path of .clang-tidy or custom config file:
  e.g. --config-file=/some/path/myTidyConfigFile
 This option internally works exactly the same way as
  --config option after reading specified config file.
 Use either --config-file or --config, not both.
-)"),
+)")),
                                        cl::init(""),
                                        cl::cat(ClangTidyCategory));
 
-static cl::opt<bool> DumpConfig("dump-config", cl::desc(R"(
+static cl::opt<bool> DumpConfig("dump-config", cl::desc(TrimFirstChar(R"(
 Dumps configuration in the YAML format to
 stdout. This option can be used along with a
 file name (and '--' if the file is outside of a
 project with configured compilation database).
 The configuration used for this file will be
 printed.
 Use along with -checks=* to include
 configuration of all checks.
-)"),
+)")),
                                 cl::init(false), cl::cat(ClangTidyCategory));
 
-static cl::opt<bool> EnableCheckProfile("enable-check-profile", cl::desc(R"(
+static cl::opt<bool> EnableCheckProfile("enable-check-profile",
+                                        cl::desc(TrimFirstChar(R"(
 Enable per-check timing profiles, and print a
 report to stderr.
-)"),
+)")),
                                         cl::init(false),
                                         cl::cat(ClangTidyCategory));
 
 static cl::opt<std::string> StoreCheckProfile("store-check-profile",
-                                              cl::desc(R"(
+                                              cl::desc(TrimFirstChar(R"(
 By default reports are printed in tabulated
 format to stderr. When this option is passed,
 these per-TU profiles are instead stored as JSON.
-)"),
+)")),
                                               cl::value_desc("prefix"),
                                               cl::cat(ClangTidyCategory));
 
 /// This option allows enabling the experimental alpha checkers from the static
 /// analyzer. This option is set to false and not visible in help, because it is
 /// highly not recommended for users.
 static cl::opt<bool>
     AllowEnablingAnalyzerAlphaCheckers("allow-enabling-analyzer-alpha-checkers",
                                        cl::init(false), cl::Hidden,
                                        cl::cat(ClangTidyCategory));
 
-static cl::opt<std::string> ExportFixes("export-fixes", cl::desc(R"(
+static cl::opt<std::string> ExportFixes("export-fixes",
+                                        cl::desc(TrimFirstChar(R"(
 YAML file to store suggested fixes in. The
 stored fixes can be applied to the input source
 code with clang-apply-replacements.
-)"),
+)")),
                                         cl::value_desc("filename"),
                                         cl::cat(ClangTidyCategory));
 
-static cl::opt<bool> Quiet("quiet", cl::desc(R"(
+static cl::opt<bool> Quiet("quiet", cl::desc(TrimFirstChar(R"(
 Run clang-tidy in quiet mode. This suppresses
 printing statistics about ignored warnings and
 warnings treated as errors if the respective
 options are specified.
-)"),
-                           cl::init(false),
-                           cl::cat(ClangTidyCategory));
+)")),
+                           cl::init(false), cl::cat(ClangTidyCategory));
 
-static cl::opt<std::string> VfsOverlay("vfsoverlay", cl::desc(R"(
+static cl::opt<std::string> VfsOverlay("vfsoverlay", cl::desc(TrimFirstChar(R"(
 Overlay the virtual filesystem described by file
 over the real file system.
-)"),
+)")),
                                        cl::value_desc("filename"),
                                        cl::cat(ClangTidyCategory));
 
-static cl::opt<bool> UseColor("use-color", cl::desc(R"(
+static cl::opt<bool> UseColor("use-color", cl::desc(TrimFirstChar(R"(
 Use colors in diagnostics. If not set, colors
 will be used if the terminal connected to
 standard output supports colors.
 This option overrides the 'UseColor' option in
 .clang-tidy file, if any.
-)"),
+)")),
                               cl::init(false), cl::cat(ClangTidyCategory));
 
-static cl::opt<bool> VerifyConfig("verify-config", cl::desc(R"(
+static cl::opt<bool> VerifyConfig("verify-config", cl::desc(TrimFirstChar(R"(
 Check the config files to ensure each check and
 option is recognized.
-)"),
+)")),
                                   cl::init(false), cl::cat(ClangTidyCategory));
 
 namespace clang::tidy {
 
 static void printStats(const ClangTidyStats &Stats) {
   if (Stats.errorsIgnored()) {
     llvm::errs() << "Suppressed " << Stats.errorsIgnored() << " warnings (";
     StringRef Separator = "";

clang-tools-extra/docs/clang-tidy/index.rst

 The ``-fix`` flag instructs :program:`clang-tidy` to fix found errors if
 supported by corresponding checks.
 
 An overview of all the command-line options:
 
 .. code-block:: console
 
   $ clang-tidy --help
+
   USAGE: clang-tidy [options] <source0> [... <sourceN>]
 
   OPTIONS:
 
   Generic Options:
 
     --help                         - Display available options (--help-hidden for more)
     --help-list                    - Display list of available options (--help-list-hidden for more)
     --version                      - Display the version of this program
 
   clang-tidy options:
 
-    --checks=<string>              -
-                                     Comma-separated list of globs with optional '-'
-                                     prefix. Globs are processed in order of
-                                     appearance in the list. Globs without '-'
-                                     prefix add checks with matching names to the
-                                     set, globs with the '-' prefix remove checks
-                                     with matching names from the set of enabled
-                                     checks. This option's value is appended to the
-                                     value of the 'Checks' option in .clang-tidy
-                                     file, if any.
-    --config=<string>              -
-                                     Specifies a configuration in YAML/JSON format:
-                                       -config="{Checks: '*',
-                                                 CheckOptions: {x, y}}"
-                                     When the value is empty, clang-tidy will
-                                     attempt to find a file named .clang-tidy for
-                                     each source file in its parent directories.
-    --config-file=<string>         -
-                                    Specify the path of .clang-tidy or custom config file:
+    --checks=<string>              - Comma-separated list of globs with optional '-'
+    --config=<string>              - Specifies a configuration in YAML/JSON format:
+                                                CheckOptions: {x: y}}"
+    --config-file=<string>         - Specify the path of .clang-tidy or custom config file:
                                       e.g. --config-file=/some/path/myTidyConfigFile
                                     This option internally works exactly the same way as
                                       --config option after reading specified config file.
                                     Use either --config-file or --config, not both.
-    --dump-config                  -
-                                     Dumps configuration in the YAML format to
-                                     stdout. This option can be used along with a
-                                     file name (and '--' if the file is outside of a
-                                     project with configured compilation database).
-                                     The configuration used for this file will be
-                                     printed.
-                                     Use along with -checks=* to include
-                                     configuration of all checks.
-    --enable-check-profile         -
-                                     Enable per-check timing profiles, and print a
-                                     report to stderr.
-    --explain-config               -
-                                     For each enabled check explains, where it is
-                                     enabled, i.e. in clang-tidy binary, command
-                                     line or a specific configuration file.
-    --export-fixes=<filename>      -
-                                     YAML file to store suggested fixes in. The
-                                     stored fixes can be applied to the input source
-                                     code with clang-apply-replacements.
-    --extra-arg=<string>           - Additional argument to append to the compiler command line.
-                                     Can be used several times.
-    --extra-arg-before=<string>    - Additional argument to prepend to the compiler command line.
-                                     Can be used several times.
-    --fix                          -
-                                     Apply suggested fixes. Without -fix-errors
-                                     clang-tidy will bail out if any compilation
-                                     errors were found.
-    --fix-errors                   -
-                                     Apply suggested fixes even if compilation
-                                     errors were found. If compiler errors have
-                                     attached fix-its, clang-tidy will apply them as
-                                     well.
-    --fix-notes                    -
-                                     If a warning has no fix, but a single fix can
-                                     be found through an associated diagnostic note,
-                                     apply the fix.
-                                     Specifying this flag will implicitly enable the
-                                     '--fix' flag.
-    --format-style=<string>        -
-                                     Style for formatting code around applied fixes:
-                                       - 'none' (default) turns off formatting
-                                       - 'file' (literally 'file', not a placeholder)
-                                         uses .clang-format file in the closest parent
-                                         directory
-                                       - '{ <json> }' specifies options inline, e.g.
-                                         -format-style='{BasedOnStyle: llvm, IndentWidth: 8}'
-                                       - 'llvm', 'google', 'webkit', 'mozilla'
-                                     See clang-format documentation for the up-to-date
-                                     information about formatting styles and options.
-                                     This option overrides the 'FormatStyle` option in
-                                     .clang-tidy file, if any.
-    --header-filter=<string>       -
-                                     Regular expression matching the names of the
-                                     headers to output diagnostics from. Diagnostics
-                                     from the main file of each translation unit are
-                                     always displayed.
-                                     Can be used together with -line-filter.
-                                     This option overrides the 'HeaderFilterRegex'
-                                     option in .clang-tidy file, if any.
-    --line-filter=<string>         -
-                                     List of files with line ranges to filter the
-                                     warnings. Can be used together with
-                                     -header-filter. The format of the list is a
-                                     JSON array of objects:
-                                       [
-                                         {"name":"file1.cpp","lines":[[1,3],[5,7]]},
-                                         {"name":"file2.h"}
-                                       ]
-    --list-checks                  -
-                                     List all enabled checks and exit. Use with
-                                     -checks=* to list all available checks.
-    -load=<plugin>                 -
-                                     Load the dynamic object ``plugin``. This
-                                     object should register new static analyzer
-                                     or clang-tidy passes. Once loaded, the
-                                     object will add new command line options
-                                     to run various analyses. To see the new
-                                     complete list of passes, use the
-                                     :option:`--list-checks` and
-                                     :option:`-load` options together.
+    --dump-config                  - Dumps configuration in the YAML format to
+    --enable-check-profile         - Enable per-check timing profiles, and print a
+    --explain-config               - For each enabled check explains, where it is
+    --export-fixes=<filename>      - YAML file to store suggested fixes in. The
+    --extra-arg=<string>           - Additional argument to append to the compiler command line
+    --extra-arg-before=<string>    - Additional argument to prepend to the compiler command line
+    --fix                          - Apply suggested fixes. Without -fix-errors
+    --fix-errors                   - Apply suggested fixes even if compilation
+    --fix-notes                    - If a warning has no fix, but a single fix can
+    --format-style=<string>        - Style for formatting code around applied fixes:
+    --header-filter=<string>       - Regular expression matching the names of the
+    --line-filter=<string>         - List of files with line ranges to filter the
+    --list-checks                  - List all enabled checks and exit. Use with
+    --load=<pluginfilename>        - Load the specified plugin
     -p <string>                    - Build path
-    --quiet                        -
-                                     Run clang-tidy in quiet mode. This suppresses
-                                     printing statistics about ignored warnings and
-                                     warnings treated as errors if the respective
-                                     options are specified.
-    --store-check-profile=<prefix> -
-                                     By default reports are printed in tabulated
-                                     format to stderr. When this option is passed,
-                                     these per-TU profiles are instead stored as JSON.
+    --quiet                        - Run clang-tidy in quiet mode. This suppresses
+    --store-check-profile=<prefix> - By default reports are printed in tabulated
     --system-headers               - Display the errors from system headers.
-    --use-color                    -
-                                    Use colors in diagnostics. If not set, colors
+    --use-color                    - Use colors in diagnostics. If not set, colors
                                     will be used if the terminal connected to
                                     standard output supports colors.
                                     This option overrides the 'UseColor' option in
                                     .clang-tidy file, if any.
-    --verify-config                -
-                                     Check the config files to ensure each check and
-                                     option is recognized.
-    --vfsoverlay=<filename>        -
-                                     Overlay the virtual filesystem described by file
-                                     over the real file system.
-    --warnings-as-errors=<string>  -
-                                     Upgrades warnings to errors. Same format as
-                                     '-checks'.
-                                     This option's value is appended to the value of
-                                     the 'WarningsAsErrors' option in .clang-tidy
-                                     file, if any.
+    --verify-config                - Check the config files to ensure each check and
+    --vfsoverlay=<filename>        - Overlay the virtual filesystem described by file
+    --warnings-as-errors=<string>  - Upgrades warnings to errors. Same format as
 
   -p <build-path> is used to read a compile command database.
 
-          For example, it can be a CMake build directory in which a file named
-          compile_commands.json exists (use -DCMAKE_EXPORT_COMPILE_COMMANDS=ON
-          CMake option to get this output). When no build path is specified,
-          a search for compile_commands.json will be attempted through all
-          parent paths of the first input file . See:
-          https://clang.llvm.org/docs/HowToSetupToolingForLLVM.html for an
-          example of setting up Clang Tooling on a source tree.
 
   <source0> ... specify the paths of source files. These paths are
-          looked up in the compile command database. If the path of a file is
-          absolute, it needs to point into CMake's source tree. If the path is
-          relative, the current working directory needs to be in the CMake
-          source tree and the file must be in a subdirectory of the current
-          working directory. "./" prefixes in the relative files will be
-          automatically removed, but the rest of a relative path must be a
-          suffix of a path in the compile command database.
 
 
   Configuration files:
     clang-tidy attempts to read configuration for each source file from a
     .clang-tidy file located in the closest parent directory of the source
-    file. If InheritParentConfig is true in a config file, the configuration file
-    in the parent directory (if any exists) will be taken and current config file
-    will be applied on top of the parent one. If any configuration options have
-    a corresponding command-line option, command-line option takes precedence.
-    The effective configuration can be inspected using -dump-config:
+    file. The .clang-tidy file is specified in YAML format. If any configuration
+    options have a corresponding command-line option, command-line option takes
+    precedence.
+
+    The following configuration options may be used in a .clang-tidy file:
+
+    CheckOptions                 - List of key-value pairs defining check-specific
+                                  options. Example:
+                                    CheckOptions:
+                                      some-check.SomeOption: 'some value'
+    Checks                       - Same as '--checks'.
+    ExtraArgs                    - Same as '--extra-args'.
+    ExtraArgsBefore              - Same as '--extra-args-before'.
+    FormatStyle                  - Same as '--format-style'.
+    HeaderFileExtensions         - File extensions to consider to determine if a
+                                  given diagnostic is located in a header file.
+                                  Default: ['','h','hh','hpp','hxx']
+    HeaderFilterRegex            - Same as '--header-filter-regex'.
+    ImplementationFileExtensions - File extensions to consider to determine if a
+                                  given diagnostic is located in an
+                                  implementation file.
+                                  Default: ['c','cc','cpp','cxx']
+    InheritParentConfig          - If this option is true in a config file, the
+                                  configuration file in the parent directory
+                                  (if any exists) will be taken and the current
+                                  config file will be applied on top of the
+                                  parent one.
+    SystemHeaders                - Same as '--system-headers'.
+    UseColor                     - Same as '--use-color'.
+    User                         - Specifies the name or e-mail of the user
+                                  running clang-tidy. This option is used, for
+                                  example, to place the correct user name in
+                                  TODO() comments in the relevant check.
+    WarningsAsErrors             - Same as '--warnings-as-errors'.
+
+    The effective configuration can be inspected using --dump-config:
 
-      $ clang-tidy -dump-config
+      $ clang-tidy --dump-config
       ---
       Checks:                       '-*,some-check'
       WarningsAsErrors:             ''
       HeaderFileExtensions:         ['', 'h','hh','hpp','hxx']
       ImplementationFileExtensions: ['c','cc','cpp','cxx']
       HeaderFilterRegex:            ''
       FormatStyle:                  none
       InheritParentConfig:          true
       User:                         user
       CheckOptions:
         some-check.SomeOption: 'some value'
       ...
 
 .. _clang-tidy-nolint:
 
 Suppressing Undesired Diagnostics
 =================================
 
 :program:`clang-tidy` diagnostics are intended to call out code that does not
 adhere to a coding standard, or is otherwise problematic in some way. However,