presubmit: add whitespace test in go (#3629)

Automatically submitted.

.benchmark.sh

@@ -1,19 +0,0 @@
-#!/usr/bin/env bash
-
-set -e +o pipefail
-
-# bit too spammy
-return
-
-if [ "$TRAVIS_PULL_REQUEST" != "false" ] ; then
-    echo -e "NOTE: The CPU benchmarks are performed on Travis VMs and vary wildly between runs," > .benchmark.body
-    echo -e " you can't trust them. The memory benchmarks are OK\n\n" >> .benchmark.body
-    awk '/^benchmark.*old/ { printf "%s\n%s\n", "```", $0 };
-         /^$/ { print "```" };
-         /^Bench/ { print $0 };
-         END{ print "```" }' .benchmark.log >> .benchmark.body
-    jq -n --arg body "$(cat .benchmark.body)" '{body: $body}' > .benchmark.json
-    curl -H "Authorization: token ${GITHUB_TOKEN}" -X POST \
-        --data-binary "@.benchmark.json" \
-        "https://api.github.com/repos/${TRAVIS_REPO_SLUG}/issues/${TRAVIS_PULL_REQUEST}/comments"
-fi

.presubmit/context

@@ -1,8 +0,0 @@
-#!/usr/bin/env bash
-
-echo "** presubmit/$(basename $0)"
-
-if grep -lr "golang.org/x/net/context" "$@"; then
-    echo "** presubmit/$(basename $0): please use std lib's 'context' instead"
-    exit 1
-fi

.presubmit/trailing-whitespace

@@ -1,7 +0,0 @@
-#!/usr/bin/env bash
-
-echo "** presubmit/$(basename $0)"
-
-if grep -r '[[:blank:]]$' "$@"; then
-    echo "** presubmit/$(basename $0): please remove any trailing white space"
-fi

test/trailing_test.go

@@ -0,0 +1,50 @@
+package test
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"unicode"
+)
+
+func TestTrailingWhitespace(t *testing.T) {
+	err := filepath.Walk("..", hasTrailingWhitespace)
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
+func hasTrailingWhitespace(path string, info os.FileInfo, _ error) error {
+	// Only handle regular files, skip files that are executable and skip file in the
+	// root that start with a .
+	if !info.Mode().IsRegular() {
+		return nil
+	}
+	if info.Mode().Perm()&0111 != 0 {
+		return nil
+	}
+	if strings.HasPrefix(path, "../.") {
+		return nil
+	}
+
+	println("looking at", path)
+	file, err := os.Open(path)
+	if err != nil {
+		return nil
+	}
+	defer file.Close()
+
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		text := scanner.Text()
+		trimmed := strings.TrimRightFunc(text, unicode.IsSpace)
+		if len(text) != len(trimmed) {
+			return fmt.Errorf("file %q has trailing whitespace, text: %q", path, text)
+		}
+	}
+
+	return scanner.Err()
+}