[fx][format-code] Allow only changed lines to be formatted.
ClangFormat supports specifying which lines should be formatted. Add
support for this in "fx format-code" by adding an option
"--changed-lines" which detects which lines have been changed in the
file (relative to the git base), and plumbs these through to
clang-format.
Change-Id: I36583222b4799289beb4501ecd51fdce2e3a320b
Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/443477
Commit-Queue: David Greenaway <dgreenaway@google.com>
Reviewed-by: Jeremy Manson <jeremymanson@google.com>
Testability-Review: Jeremy Manson <jeremymanson@google.com>
diff --git a/tools/devshell/contrib/format-code b/tools/devshell/contrib/format-code
index e1d2c54..a9fd40f 100755
--- a/tools/devshell/contrib/format-code
+++ b/tools/devshell/contrib/format-code
@@ -10,7 +10,7 @@
## [--dry-run] [--verbose] [--all]
## [--files=FILES,[FILES ...]]
## [--target=GN_TARGET]
-## [--git] [-- PATTERN]
+## [--git] [--changed-lines] [-- PATTERN]
##
## --dry-run Stops the program short of running the formatters
## --all Formats all code in the git repo under the current working
@@ -23,6 +23,11 @@
## commit in the upstream branch (or against HEAD if no such commit
## is found). Files that are locally modified, staged or touched by
## any commits introduced on the local branch are formatted.
+## --changed-lines
+## Format changed lines only. Only supported on a subset of languages
+## (currently, just C++). Unsupported languages will continue to have
+## the entire file formatted. "Changes" are relative to the git
+## commit that would be used by "--git".
## --verbose Print all formatting commands prior to execution.
## -- PATTERN
## For --all or --git, passes along -- PATTERN to `git ls-files`
@@ -53,28 +58,59 @@
fi
}
-function format-cmd() {
- if [ -f "$1" ]; then
- case "$1" in
- *.c | *.cc | *.cpp | *.h | *.hh | *.hpp | *.proto | *.ts)
- printf "${CLANG_CMD}" ;;
+# Execute a command, printing it first if VERBOSE is set.
+function print-and-execute() {
+ if [[ -n "${VERBOSE}" ]]; then
+ echo "$@"
+ fi
+ "$@"
+}
- *.cmx) printf "${JSON_FMT_CMD}" ;;
- *.cml) printf "${CML_FMT_CMD}" ;;
- *.dart) printf "${DART_CMD}" ;;
- *.fidl) printf "${FIDL_CMD}" ;;
- *.gn) printf "${GN_CMD}" ;;
- *.gni) printf "${GN_CMD}" ;;
- *.go) printf "${GO_CMD}" ;;
- *.py) printf "${PY_CMD}" ;;
- *.rs) printf "${RUST_FMT_CMD}" ;;
- *.triage) printf "${JSON5_FMT_CMD}" ;;
- esac
+# Format the given C++ file.
+function format-cc-file() {
+ if [[ -n ${CHANGED_LINES} ]]; then
+ # Only update changed lines.
+ local changed_line_commands=$(git-print-changed-lines "$1" "--lines=%dF:%dL ")
+ if [[ -n ${changed_line_commands} ]]; then
+ print-and-execute ${CLANG_CMD} ${changed_line_commands} "$1"
+ fi
+ else
+ # Update entire files.
+ print-and-execute ${CLANG_CMD} "$1"
+ fi
+ # Unconditionally update header guards.
+ if [[ $1 =~ .*\.h ]]; then
+ print-and-execute ${FIX_HEADER_GUARDS_CMD} "$1"
fi
}
-function hg-cmd() {
- [[ $1 =~ .*\.h ]] && printf "${FIX_HEADER_GUARDS_CMD}"
+# Run the given format command on a single file, warning if "CHANGED_LINES" is set.
+function format-full-file() {
+ local command="$1"
+ local file="$2"
+ if [ -n "${CHANGED_LINES}" ]; then
+ echo "Warning: cannot format only modified lines; formatting full file ${file}" >&2
+ fi
+ print-and-execute ${command} "${file}"
+}
+
+# Format the given file.
+function format-file() {
+ case "$1" in
+ *.c | *.cc | *.cpp | *.h | *.hh | *.hpp | *.proto | *.ts)
+ format-cc-file "$1" ;;
+
+ *.cmx) format-full-file "${JSON_FMT_CMD}" "$1" ;;
+ *.cml) format-full-file "${CML_FMT_CMD}" "$1";;
+ *.dart) format-full-file "${DART_CMD}" "$1";;
+ *.fidl) format-full-file "${FIDL_CMD}" "$1" ;;
+ *.gn) format-full-file "${GN_CMD}" "$1" ;;
+ *.gni) format-full-file "${GN_CMD}" "$1" ;;
+ *.go) format-full-file "${GO_CMD}" "$1" ;;
+ *.py) format-full-file "${PY_CMD}" "$1" ;;
+ *.rs) format-full-file "${RUST_FMT_CMD}" "$1" ;;
+ *.triage) format-full-file "${JSON5_FMT_CMD}" "$1";;
+ esac
}
# Removes leading //, resolves to absolute path, and resolves globs. The first
@@ -98,6 +134,7 @@
DRY_RUN=
VERBOSE=
+CHANGED_LINES=
fx-config-read
@@ -107,6 +144,7 @@
case "$1" in
--verbose) VERBOSE="1" ;;
--dry-run) DRY_RUN="1" ;;
+ --changed-lines) CHANGED_LINES="1" ;;
--all) GET_FILES=get_all_files ;;
--git) GET_FILES=get_git_files ;;
--files=*)
@@ -136,6 +174,20 @@
FILES=$(canonicalize "${PWD}" $(git ls-files "${GIT_FILTER[@]}"))
}
+# Print lines changed in the given file.
+#
+# "Changes" are calculated relative to `git-diff-base`.
+git-print-changed-lines() {
+ # Have git run `/usr/bin/diff` on the input file.
+ #
+ # We in turn ask `diff` to print for each new or modified line the format
+ # string in `$2`. Details about the format string can be found in the man
+ # page for diff, under `--new-group-format`.
+ git difftool -y \
+ -x "diff --new-group-format='$2' --line-format=''" \
+ $(get-diff-base) -- "$1"
+}
+
$GET_FILES
# Do not format these files
@@ -193,33 +245,29 @@
[[ -n "${RUST_ENTRY_POINT}" ]] && ${RUST_ENTRY_POINT_FMT_CMD} "${RUST_ENTRY_POINT}"
-declare HAS_MARKDOWN=
+# Format files.
for file in ${FILES[@]}; do
# Git reports deleted files, which we don't want to try to format
[[ ! -f "${file}" ]] && continue
# Format the file
- declare fcmd=$(format-cmd ${file})
- declare hgcmd=$(hg-cmd ${file})
- if [[ -n "${VERBOSE}" ]]; then
- echo ${fcmd} "${file}"
- fi
- [[ -n "${fcmd}" ]] && ${fcmd} "${file}"
- [[ -n "${hgcmd}" ]] && ${hgcmd} "${file}"
+ format-file ${file}
+done
- # Collect markdown
+# If a Markdown change is present (including a deletion of a markdown file),
+# check the entire project.
+declare HAS_MARKDOWN=
+for file in ${FILES[@]}; do
if [[ ${file} == *.md ]]; then
HAS_MARKDOWN="1";
fi
done
-
-# Markdown change detected, check entire project
if [[ -n "${HAS_MARKDOWN}" ]]; then
if [[ ! -x "${MARKDOWN_FMT_TOOL_ABS}" ]] ; then
fx-info "doc-checker not built; building now..."
fx-command-run build --no-zircon "${MARKDOWN_FMT_TOOL}"
fi
- "${MARKDOWN_FMT_TOOL_ABS}" --local-links-only --root "${FUCHSIA_DIR}";
+ print-and-execute "${MARKDOWN_FMT_TOOL_ABS}" --local-links-only --root "${FUCHSIA_DIR}";
fi
# The last thing this script does is often the [[ -n "${hgcmd}" ]], which will
