build: Add some smarts to IWYU script

If passing a commit to tools/run_iwyu.sh, check only the files changed
in that commit or later, including uncommitted files. This allows
running IWYU with much less friction and opens the door to running it
automatically in CI.

1 files changed, 47 insertions, 2 deletions

diff --git a/tools/run_iwyu.sh b/tools/run_iwyu.sh
index 5773289f..e67f4818 100755
--- a/tools/run_iwyu.sh
+++ b/tools/run_iwyu.sh
@@ -2,6 +2,35 @@
 
 SRCDIR=$(pwd)
 
+if [ "$1" == '--help' -o "$1" == '-h' ]; then
+    echo "usage: $0 [ COMMIT ]"
+    echo "Run include-what-you-use on the GJS codebase."
+    echo "If COMMIT is given, analyze only the files changed since that commit,"
+    echo "including uncommitted changes."
+    echo "Otherwise, analyze all files."
+    exit 0
+fi
+
+if [ $# -eq 0 ]; then
+    files=all
+else
+    files="$(git diff-tree --name-only -r $1..) $(git diff-index --name-only HEAD)"
+fi
+
+echo "files: $files"
+
+should_analyze () {
+    file=$(realpath --relative-to=$SRCDIR $1)
+    case "$files" in
+        all) return 0 ;;
+        *$file*) return 0 ;;
+        *${file%.cpp}.h*) return 0 ;;
+        *${file%.cpp}-private.h*) return 0 ;;
+        *${file%.c}.h*) return 0 ;;
+        *) return 1 ;;
+    esac
+}
+
 cd ${BUILDDIR:-_build}
 if ! ninja; then
     echo 'Build failed.'
@@ -23,24 +52,40 @@ for FILE in $SRCDIR/gi/*.cpp $SRCDIR/gjs/atoms.cpp $SRCDIR/gjs/byteArray.cpp \
     $SRCDIR/modules/system.cpp $SRCDIR/test/*.cpp $SRCDIR/util/*.cpp \
     $SRCDIR/libgjs-private/*.c
 do
-    $IWYU $FILE -- $PRIVATE_MAPPING | $POSTPROCESS
+    should_analyze $FILE && $IWYU $FILE -- $PRIVATE_MAPPING | $POSTPROCESS
 done
+
+should_analyze $SRCDIR/gjs/context.cpp && \
 $IWYU $SRCDIR/gjs/context.cpp -- $PRIVATE_MAPPING \
     -Xiwyu --check_also=*/gjs/context-private.h | $POSTPROCESS
+
+( should_analyze $SRCDIR/gjs/jsapi-dynamic-class.cpp || \
+    should_analyze $SRCDIR/gjs/jsapi-class.h ) && \
 $IWYU $SRCDIR/gjs/jsapi-dynamic-class.cpp -- $PRIVATE_MAPPING \
     -Xiwyu --check_also=*/gjs/jsapi-class.h | $POSTPROCESS
+
+( should_analyze $SRCDIR/gjs/jsapi-util.cpp ||
+    should_analyze $SRCDIR/gjs/jsapi-util-args.h || \
+    should_analyze $SRCDIR/gjs/jsapi-util-root.h ) && \
 $IWYU $SRCDIR/gjs/jsapi-util.cpp -- $PRIVATE_MAPPING \
     -Xiwyu --check_also=*/gjs/jsapi-util-args.h \
     -Xiwyu --check_also=*/gjs/jsapi-util-root.h | $POSTPROCESS
+
+should_analyze $SRCDIR/gjs/mem.cpp && \
 $IWYU $SRCDIR/gjs/mem.cpp -- $PRIVATE_MAPPING \
     -Xiwyu --check_also=*/gjs/mem-private.h | $POSTPROCESS
+
+should_analyze $SRCDIR/gjs/profiler.cpp && \
 $IWYU $SRCDIR/gjs/profiler.cpp -- $PRIVATE_MAPPING \
     -Xiwyu --check_also=*/gjs/profiler-private.h | $POSTPROCESS
+
+( should_analyze $SRCDIR/modules/cairo.cpp ||
+    should_analyze $SRCDIR/modules/cairo-module.h ) && \
 $IWYU $SRCDIR/modules/cairo.cpp -- $PRIVATE_MAPPING \
     -Xiwyu --check_also=*/modules/cairo-module.h \
     -Xiwyu --check_also=*/modules/cairo-private.h | $POSTPROCESS
 
 for FILE in $SRCDIR/gjs/console.cpp $SRCDIR/installed-tests/minijasmine.cpp
 do
-    $IWYU $FILE -- $PUBLIC_MAPPING | $POSTPROCESS
+    should_analyze $FILE && $IWYU $FILE -- $PUBLIC_MAPPING | $POSTPROCESS
 done