check_clang_tidy_fix.sh: added comments, use set -o errexit instead of '|| exit $?' on each command

llvm-svn: 214956

clang-tools-extra/test/clang-tidy/check_clang_tidy_fix.sh

@@ -1,25 +1,34 @@
 #!/bin/sh
 #
 # Run clang-tidy in fix mode and verify the result.
+# Usage:
+#   check_clang_tidy_fix.sh <source-file> <check-name> <temp-file> \
+#     [optional compiler arguments]
+#
+# Example:
+#   // RUN: $(dirname %s)/check_clang_tidy_fix.sh %s llvm-include-order %t -isystem $(dirname %s)/Inputs/Headers
+#   // REQUIRES: shell
 
 INPUT_FILE=$1
 CHECK_TO_RUN=$2
 TEMPORARY_FILE=$3.cpp
+# Feed the rest arguments to clang-tidy after --.
 shift 3
 
+set -o errexit
+
 # Remove the contents of the CHECK lines to avoid CHECKs matching on themselves.
 # We need to keep the comments to preserve line numbers while avoiding empty
 # lines which could potentially trigger formatting-related checks.
 sed 's#// *[A-Z-]\+:.*#//#' ${INPUT_FILE} > ${TEMPORARY_FILE}
 
-clang-tidy ${TEMPORARY_FILE} -fix --checks="-*,${CHECK_TO_RUN}" -- --std=c++11 \
-  $* > ${TEMPORARY_FILE}.msg 2>&1 || exit $?
+clang-tidy ${TEMPORARY_FILE} -fix --checks="-*,${CHECK_TO_RUN}" \
+  -- --std=c++11 $* > ${TEMPORARY_FILE}.msg 2>&1
 
 FileCheck -input-file=${TEMPORARY_FILE} ${INPUT_FILE} \
-  -check-prefix=CHECK-FIXES -strict-whitespace || exit $?
+  -check-prefix=CHECK-FIXES -strict-whitespace
 
 if grep -q CHECK-MESSAGES ${INPUT_FILE}; then
   FileCheck -input-file=${TEMPORARY_FILE}.msg ${INPUT_FILE} \
-    -check-prefix=CHECK-MESSAGES -implicit-check-not="{{warning|error}}:" \
-    || exit $?
+    -check-prefix=CHECK-MESSAGES -implicit-check-not="{{warning|error}}:"
 fi