Add quickgogen command to gogen touched directories/files

bin/quickgogen

@@ -0,0 +1 @@
+../scripts/dev/quickgogen.sh

lib/git.sh

@@ -11,6 +11,22 @@ function get_current_branch() {
   echo "${ref#refs/heads/}"
 }
 
+# Gets the main branch or dies.
+function get_main_branch_or_die() {
+  # From https://stackoverflow.com/questions/28666357/git-how-to-get-default-branch#comment92366240_50056710
+  local main_branch
+  main_branch="$(git remote show origin | grep "HEAD branch" | sed 's/.*: //')"
+  [[ -n "${main_branch}" ]] || die "Failed to get main branch"
+  echo "${main_branch}"
+}
+
+# Gets the diffbase off of the remote's main branch or dies.
+function get_diffbase_or_die() {
+  diffbase="$(git merge-base HEAD "origin/${main_branch}")"
+  [[ $? -eq 0 ]] || die "Failed to determine diffbase"
+  echo "${diffbase}"
+}
+
 function get_remote() {
   local remote
   remote="$(git config --get remote.origin.url)"
@@ -67,3 +83,13 @@ function branch_exists() {
 	local branch="$1"
 	git show-ref --verify --quiet "refs/heads/$branch"
 }
+
+# TODO(do-not-merge): How return multi-line output properly?
+# Requires $gitroot.
+# Returns the list of .go file paths in $gitroot (with $gitroot prefix)
+# that have a comment saying they are generated files.
+function quick_get_generated_files {
+  echo "$(git -C "$gitroot" \
+    grep -l '^// Code generated by .* DO NOT EDIT\.' -- '*.go' | \
+    sed -e "s@^@${gitroot}/@")"
+}

scripts/dev/quickgogen.sh

@@ -0,0 +1,64 @@
+#!/usr/bin/env bash
+
+# Usage: Runs gogen for all Go files that have changed between the current code and master.
+
+SCRIPT="$(python -c 'import os, sys; print(os.path.realpath(sys.argv[1]))' "${BASH_SOURCE[0]}")"
+source "$(dirname "$SCRIPT")/../../lib/common.sh"
+source "$(dirname "$SCRIPT")/../../lib/git.sh"
+
+gitroot="$(git rev-parse --show-toplevel)"
+[[ $? -eq 0 ]] || die "Current directory is not a git repository."
+
+if [[ -f "${gitroot}/go.mod" ]]; then
+	export GO111MODULE=on
+fi
+
+# Various code generation helpers are expected to be in the PATH when called by go generate.
+export PATH="$PATH:${gitroot}/tools/generate-helpers"
+
+main_branch="$(get_main_branch_or_die)"
+diffbase="$(get_diffbase_or_die)"
+
+generated_files="$(git -C "$gitroot" grep -l '^// Code generated by .* DO NOT EDIT\.' -- '*.go' | sed -e "s@^@${gitroot}/@")"
+
+IFS=$'\n' read -d '' -r -a changed_files < <(
+	{
+		git diff "$diffbase" --name-status . |
+		sed -n -E -e "s@^[AM][[:space:]]+|^R[^[:space:]]*[[:space:]]+[^[:space:]]+[[:space:]]+@${gitroot}/@p" ;
+		echo "$generated_files" ; echo "$generated_files"
+} | sort | uniq -u) || true
+
+function private_gogen() {
+	local status=0
+	local changed_files=("$@")
+	local gofiles
+
+	IFS=$'\n' read -d '' -r -a gofiles < <(
+		printf '%s\n' "${changed_files[@]}" |
+		grep '\.go$'
+	)
+	[[ "${#gofiles[@]}" == 0 ]] && return 0
+
+	IFS=$'\n' read -d '' -r -a godirs < <(
+		for f in "${gofiles[@]}"; do dirname "$f"; done |
+		sort | uniq)
+
+	einfo "Running go generate..."
+	for dir in "${godirs[@]}"; do
+		einfo "...Generating for ${dir}"
+		( cd "$dir" && go generate "./" ) && (( status == 0 ))
+		status=$?
+	done
+
+	return "${status}"
+}
+
+[[ "${#changed_files[@]}" -eq 0 ]] && { ewarn "No relevant changes found in current directory."; exit 0; }
+status=0
+
+private_gogen "${changed_files[@]}" && (( status == 0 ))
+status=$?
+
+[[ "${status}" -eq 0 ]] && exit 0
+efatal "An error occurred while generating files"
+exit 1

scripts/dev/quickstyle.sh

@@ -8,6 +8,7 @@
 SCRIPT="$(python -c 'import os, sys; print(os.path.realpath(sys.argv[1]))' "${BASH_SOURCE[0]}")"
 source "$(dirname "$SCRIPT")/../../lib/common.sh"
 source "$(dirname "$SCRIPT")/../../setup/packages.sh"
+source "$(dirname "$SCRIPT")/../../lib/git.sh"
 
 check_dependencies
 
@@ -222,12 +223,8 @@ if [[ -f "${gitroot}/go.mod" ]]; then
 	export GO111MODULE=on
 fi
 
-# https://stackoverflow.com/a/44750379
-main_branch="$(git symbolic-ref refs/remotes/origin/HEAD | sed 's@^refs/remotes/origin/@@')"
-[[ -n "${main_branch}" ]] || die "Failed to get main branch"
-
-diffbase="$(git merge-base HEAD "origin/${main_branch}")"
-[[ $? -eq 0 ]] || die "Failed to determine diffbase"
+main_branch="$(get_main_branch_or_die)"
+diffbase="$(get_diffbase_or_die)"
 
 generated_files="$(git -C "$gitroot" grep -l '^// Code generated by .* DO NOT EDIT\.' -- '*.go' | sed -e "s@^@${gitroot}/@")"