[clang-tidy] Fix the order of ExtraArgsBefore

Added tests for the relative order of -extra-arg(-before) and ExtraArgs(Before).

llvm-svn: 279516

clang-tools-extra/clang-tidy/ClangTidy.cpp

@@ -426,10 +426,14 @@ runClangTidy(std::unique_ptr<ClangTidyOptionsProvider> OptionsProvider,
   ArgumentsAdjuster PerFileExtraArgumentsInserter =
       [&Context](const CommandLineArguments &Args, StringRef Filename) {
         ClangTidyOptions Opts = Context.getOptionsForFile(Filename);
-        CommandLineArguments AdjustedArgs;
+        CommandLineArguments AdjustedArgs = Args;
-        if (Opts.ExtraArgsBefore)
+        if (Opts.ExtraArgsBefore) {
-          AdjustedArgs = *Opts.ExtraArgsBefore;
+          auto I = AdjustedArgs.begin();
-        AdjustedArgs.insert(AdjustedArgs.begin(), Args.begin(), Args.end());
+          if (I != AdjustedArgs.end() && !StringRef(*I).startswith("-"))
+            ++I; // Skip compiler binary name, if it is there.
+          AdjustedArgs.insert(I, Opts.ExtraArgsBefore->begin(),
+                              Opts.ExtraArgsBefore->end());
+        }
         if (Opts.ExtraArgs)
           AdjustedArgs.insert(AdjustedArgs.end(), Opts.ExtraArgs->begin(),
                               Opts.ExtraArgs->end());

clang-tools-extra/test/clang-tidy/custom-diagnostics.cpp

@@ -1,7 +1,22 @@
 // RUN: clang-tidy -checks='-*,modernize-use-override,clang-diagnostic-shadow,clang-diagnostic-float-conversion' %s -- | count 0
+//
+// Enable warnings using -config:
 // RUN: clang-tidy -checks='-*,modernize-use-override,clang-diagnostic-shadow,clang-diagnostic-float-conversion' \
 // RUN:   -config='{ExtraArgs: ["-Wshadow","-Wno-unused-variable"], ExtraArgsBefore: ["-Wno-shadow","-Wfloat-conversion","-Wunused-variable"]}' %s -- \
 // RUN:   | FileCheck -implicit-check-not='{{warning:|error:}}' %s
+//
+// ... -extra-arg:
+// RUN: clang-tidy -checks='-*,modernize-use-override,clang-diagnostic-shadow,clang-diagnostic-float-conversion' \
+// RUN:   -extra-arg=-Wshadow -extra-arg=-Wno-unused-variable \
+// RUN:   -extra-arg-before=-Wno-shadow -extra-arg-before=-Wfloat-conversion \
+// RUN:   -extra-arg-before=-Wunused-variable %s -- \
+// RUN:   | FileCheck -implicit-check-not='{{warning:|error:}}' %s
+//
+// ... a combination of -config and -extra-arg(-before):
+// RUN: clang-tidy -checks='-*,modernize-use-override,clang-diagnostic-shadow,clang-diagnostic-float-conversion' \
+// RUN:   -config='{ExtraArgs: ["-Wno-unused-variable"], ExtraArgsBefore: ["-Wno-shadow","-Wfloat-conversion"]}' \
+// RUN:   -extra-arg=-Wshadow -extra-arg-before=-Wunused-variable %s -- \
+// RUN:   | FileCheck -implicit-check-not='{{warning:|error:}}' %s
 
 void f(float x) {
   int a;

clang-tools-extra/test/clang-tidy/extra-args.cpp

@@ -0,0 +1,7 @@
+// RUN: clang-tidy -checks='-*,modernize-use-override' \
+// RUN:   -config='{ExtraArgs: ["-DTEST4"], ExtraArgsBefore: ["-DTEST1"]}' \
+// RUN:   -extra-arg=-DTEST3 -extra-arg-before=-DTEST2 %s -- -v 2>&1 \
+// RUN:   | FileCheck -implicit-check-not='{{warning:|error:}}' %s
+
+// CHECK: {{^}}clang Invocation:{{$}}
+// CHECK-NEXT: {{"-D" "TEST1" .*"-D" "TEST2" .*"-D" "TEST3" .*"-D" "TEST4"}}