My goal is to enforce the formatting of go source code on commit. Is there a way to find out if running go fmt over a file/set of files would make any changes? The only technique I can think of is to:
I could write a tool/script to do this and execute during circle CI build. I wanted to check that I'm not reinventing the wheel before I go ahead.
According to gofmt -h you can use -l option:
-l list files whose formatting differs from gofmt's`
Something like:
> gofmt -l .
And pass the received list of files further.
I found this pre-commit hook enter link description here
1 #!/bin/sh
2 # Copyright 2012 The Go Authors. All rights reserved.
3 # Use of this source code is governed by a BSD-style
4 # license that can be found in the LICENSE file.
5
6 # git gofmt pre-commit hook
7 #
8 # To use, store as .git/hooks/pre-commit inside your repository and make sure
9 # it has execute permissions.
10 #
11 # This script does not handle file names that contain spaces.
12
13 gofiles=$(git diff --cached --name-only --diff-filter=ACM | grep '\.go$')
14 [ -z "$gofiles" ] && exit 0
15
16 unformatted=$(gofmt -l $gofiles)
17 [ -z "$unformatted" ] && exit 0
18
19 # Some files are not gofmt'd. Print message and fail.
20
21 echo >&2 "Go files must be formatted with gofmt. Please run:"
22 for fn in $unformatted; do
23 echo >&2 " gofmt -w $PWD/$fn"
24 done
25
26 exit 1