Filter out unwanted stderr output during git push commands

samcoe · samcoe · commit 06586228f3b2 · 2020-10-07T14:03:41.000+02:00
diff --git a/git/git.go b/git/git.go
@@ -12,6 +12,7 @@ import (
 	"strings"
 
 	"github.com/cli/cli/internal/run"
+	"github.com/cli/cli/pkg/iostreams"
 )
 
 // ErrNotOnAnyBranch indicates that the user is in detached HEAD state
@@ -164,8 +165,10 @@ func CommitBody(sha string) (string, error) {
 // Push publishes a git ref to a remote and sets up upstream configuration
 func Push(remote string, ref string) error {
 	pushCmd := GitCommand("push", "--set-upstream", remote, ref)
+	regexp := regexp.MustCompile("^remote:.*$")
+	filterErr := iostreams.NewRegexFilterWriter(os.Stderr, regexp, "")
 	pushCmd.Stdout = os.Stdout
-	pushCmd.Stderr = os.Stderr
+	pushCmd.Stderr = filterErr
 	return run.PrepareCmd(pushCmd).Run()
 }
 
diff --git a/pkg/iostreams/regex_filter_writer.go b/pkg/iostreams/regex_filter_writer.go
@@ -0,0 +1,46 @@
+package iostreams
+
+import (
+	"bufio"
+	"bytes"
+	"io"
+	"regexp"
+)
+
+func NewRegexFilterWriter(out io.Writer, regexp *regexp.Regexp, repl string) io.Writer {
+	return &RegexFilterWriter{out: out, regexp: *regexp, repl: repl}
+}
+
+type RegexFilterWriter struct {
+	out    io.Writer
+	regexp regexp.Regexp
+	repl   string
+}
+
+func (s RegexFilterWriter) Write(data []byte) (int, error) {
+	filtered := []byte{}
+	repl := []byte(s.repl)
+	scanner := bufio.NewScanner(bytes.NewReader(data))
+
+	for scanner.Scan() {
+		b := scanner.Bytes()
+		f := s.regexp.ReplaceAll(b, repl)
+		if len(f) > 0 {
+			filtered = append(filtered, f...)
+			filtered = append(filtered, []byte("\n")...)
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		return 0, err
+	}
+
+	if len(filtered) != 0 {
+		_, err := s.out.Write(filtered)
+		if err != nil {
+			return 0, err
+		}
+	}
+
+	return len(data), nil
+}
diff --git a/pkg/iostreams/regex_filter_writer_test.go b/pkg/iostreams/regex_filter_writer_test.go
@@ -0,0 +1,143 @@
+package iostreams
+
+import (
+	"bytes"
+	"regexp"
+	"testing"
+
+	"github.com/MakeNowJust/heredoc"
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_Write(t *testing.T) {
+	type input struct {
+		in     string
+		regexp *regexp.Regexp
+		repl   string
+	}
+	type output struct {
+		wantsErr bool
+		out      string
+		length   int
+	}
+	tests := []struct {
+		name   string
+		input  input
+		output output
+	}{
+		{
+			name: "single line input",
+			input: input{
+				in:     "some input line that has wrong information",
+				regexp: regexp.MustCompile("wrong"),
+				repl:   "right",
+			},
+			output: output{
+				wantsErr: false,
+				out:      "some input line that has right information\n",
+				length:   42,
+			},
+		},
+		{
+			name: "multiple line input",
+			input: input{
+				in:     "multiple lines\nin this\ninput lines",
+				regexp: regexp.MustCompile("lines"),
+				repl:   "tests",
+			},
+			output: output{
+				wantsErr: false,
+				out:      "multiple tests\nin this\ninput tests\n",
+				length:   34,
+			},
+		},
+		{
+			name: "no matches",
+			input: input{
+				in:     "this line has no matches",
+				regexp: regexp.MustCompile("wrong"),
+				repl:   "right",
+			},
+			output: output{
+				wantsErr: false,
+				out:      "this line has no matches\n",
+				length:   24,
+			},
+		},
+		{
+			name: "no output",
+			input: input{
+				in:     "remove this whole line",
+				regexp: regexp.MustCompile("^remove.*$"),
+				repl:   "",
+			},
+			output: output{
+				wantsErr: false,
+				out:      "",
+				length:   22,
+			},
+		},
+		{
+			name: "no input",
+			input: input{
+				in:     "",
+				regexp: regexp.MustCompile("remove"),
+				repl:   "",
+			},
+			output: output{
+				wantsErr: false,
+				out:      "",
+				length:   0,
+			},
+		},
+		{
+			name: "multiple lines removed",
+			input: input{
+				in:     "begining line\nremove this whole line\nremove this one also\nnot this one",
+				regexp: regexp.MustCompile("^remove.*$"),
+				repl:   "",
+			},
+			output: output{
+				wantsErr: false,
+				out:      "begining line\nnot this one\n",
+				length:   70,
+			},
+		},
+		{
+			name: "removes remote from git push output",
+			input: input{
+				in: heredoc.Doc(`
+					output: some information
+					remote:
+					remote: Create a pull request for 'regex' on GitHub by visiting:
+					remote:      https://github.com/owner/repo/pull/new/regex
+					remote:
+					output: more information
+			 `),
+				regexp: regexp.MustCompile("^remote.*$"),
+				repl:   "",
+			},
+			output: output{
+				wantsErr: false,
+				out:      "output: some information\noutput: more information\n",
+				length:   189,
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		out := &bytes.Buffer{}
+		writer := NewRegexFilterWriter(out, tt.input.regexp, tt.input.repl)
+		t.Run(tt.name, func(t *testing.T) {
+			length, err := writer.Write([]byte(tt.input.in))
+
+			if tt.output.wantsErr {
+				assert.Error(t, err)
+				return
+			}
+			assert.NoError(t, err)
+			assert.Equal(t, tt.output.out, out.String())
+			assert.Equal(t, tt.output.length, length)
+		})
+	}
+}
