[Clang][ScanDeps] Change multiple-commands.c test to use -fmodules-cache-path on implicit builds

[bruno]

Summary

The module cache escapes the test output dirs in this test. Since its default location maybe
composed of system and user related path this can cause problems in some builders (e.g. not
accessible paths inherited in a chroot environment).

Clean the test a bit by passing -fmodules-cache-path inside the test output dirs.

[benlangmuir]

Thanks for catching this!

clang/test/ClangScanDeps/multiple-commands.c

11

Nit: we could just put it inside DIR/modcache and not need a second substitution.

[jansvoboda11]

LGTM, thanks! Though we usually put the cache directory into %t/cache (aka DIR/cache in the JSON file) in other scanner tests, which would allow you to drop the second sed expression. (And you'd want to rm -rf %t instead.)

[bruno]

Thanks for the fast review! Good suggestions, will apply and land.

[benlangmuir]

Attempting to not do this again: https://reviews.llvm.org/D133622

clang/test/ClangScanDeps/multiple-commands.c

 // Test scanning when the driver requires multiple jobs. E.g. with -save-temps
 // there will be separate -E, -emit-llvm-bc, -S, and -cc1as jobs, which should
 // each result in a "command" in the output.
 
 // We use an x86_64-apple-darwin target to avoid host-dependent behaviour in
 // the driver. Platforms without an integrated assembler have different commands
 // REQUIRES: x86-registered-target
 
 // RUN: rm -rf %t
 // RUN: split-file %s %t
 // RUN: sed -e "s|DIR|%/t|g" %t/cdb.json.in > %t/cdb.json
 
 // RUN: clang-scan-deps -compilation-database %t/cdb.json -module-files-dir %t/modules \
 // RUN:   -j 1 -format experimental-full -mode preprocess-dependency-directives \
 // RUN:   > %t/deps.json
 
 // RUN: cat %t/deps.json | sed 's:\\\\\?:/:g' | FileCheck %s -DPREFIX=%/t
 
 // Build the -save-temps + -fmodules case

 [
   {
     "directory": "DIR"
     "command": "clang_tool -target x86_64-apple-darwin -c DIR/tu_no_integrated_cpp.c -no-integrated-cpp -o DIR/tu_no_integrated_cpp.o"
     "file": "DIR/tu_no_integrated_cpp.c"
   },
   {
     "directory": "DIR"
-    "command": "clang_tool -target x86_64-apple-darwin -c DIR/tu_save_temps_module.c -save-temps=obj -o DIR/tu_save_temps_module.o -fmodules -fimplicit-modules -fimplicit-module-maps"
+    "command": "clang_tool -target x86_64-apple-darwin -c DIR/tu_save_temps_module.c -save-temps=obj -o DIR/tu_save_temps_module.o -fmodules -fimplicit-modules -fimplicit-module-maps -fmodules-cache-path=DIR/cache"
     "file": "DIR/tu_save_temps_module.c"
   }
 ]
 
 //--- plain_header.h
 void foo(void);
 
 //--- module_header.h