🚧 Write hook message to file

Write hook message to file that can be read by Git.

internal/repository/commit.go

@@ -2,28 +2,49 @@ package repository
 
 import (
 	"fmt"
+	"io"
 	"os"
 )
 
 type Commit struct {
-	Author  string
-	Subject string
-	Body    string
-	Footer  string
-	Amend   bool
-	DryRun  bool
+	Author      string
+	Subject     string
+	Body        string
+	Footer      string
+	Amend       bool
+	DryRun      bool
+	Hook        bool
+	MessageFile string
 }
 
 const command = "git"
 
 func (r *Repository) Apply(c Commit) error {
+	if c.Hook {
+		return r.hook(c)
+	}
+
 	if err := r.Runner(os.Stdout, command, build(c)); err != nil {
 		return fmt.Errorf("unable to run command: %w", err)
 	}
 
 	return nil
 }
 
+func (r *Repository) hook(c Commit) error {
+	fh, err := r.OpenFiler(c.MessageFile, os.O_RDWR|os.O_TRUNC, 0o0755)
+	if err != nil {
+		return fmt.Errorf("unble to open file: %w", err)
+	}
+
+	err = write(c, fh)
+	if err != nil {
+		return fmt.Errorf("unable to write file: %w", err)
+	}
+
+	return nil
+}
+
 func build(c Commit) []string {
 	var args []string
 
@@ -49,3 +70,25 @@ func build(c Commit) []string {
 
 	return args
 }
+
+func write(c Commit, w io.WriteCloser) error {
+	var err error
+
+	fmt.Fprintln(w, c.Subject)
+	fmt.Fprintln(w, "")
+
+	if c.Body != "" {
+		fmt.Fprintln(w, c.Body)
+		fmt.Fprintln(w, "")
+	}
+
+	if c.Footer != "" {
+		fmt.Fprintln(w, c.Footer)
+	}
+
+	if err = w.Close(); err != nil {
+		return fmt.Errorf("unable to close file: %w", err)
+	}
+
+	return nil
+}

internal/repository/commit_test.go

@@ -3,6 +3,8 @@ package repository_test
 import (
 	"errors"
 	"io"
+	"os"
+	"strings"
 	"testing"
 
 	"github.com/mikelorant/committed/internal/repository"
@@ -29,21 +31,52 @@ func (r *MockShell) Run() func(w io.Writer, command string, args []string) error
 	}
 }
 
+type MockOpenFile struct {
+	filename     string
+	mockFilename string
+	err          error
+	close        bool
+}
+
+func (o *MockOpenFile) OpenFile() func(string, int, os.FileMode) (*os.File, error) {
+	return func(filename string, flag int, perm os.FileMode) (*os.File, error) {
+		if o.err != nil {
+			return nil, o.err
+		}
+
+		fh, _ := os.CreateTemp("", "")
+
+		o.filename = filename
+		o.mockFilename = fh.Name()
+
+		if o.close {
+			fh.Close()
+		}
+
+		return fh, nil
+	}
+}
+
 var errMock = errors.New("error")
 
 func TestApply(t *testing.T) {
 	t.Parallel()
 
 	type args struct {
-		commit repository.Commit
-		opts   []func(c *repository.Commit)
-		err    error
+		commit      repository.Commit
+		opts        []func(c *repository.Commit)
+		filename    string
+		runErr      error
+		openFileErr error
+		close       bool
 	}
 
 	type want struct {
-		cmd  string
-		args []string
-		err  error
+		cmd          string
+		args         []string
+		data         string
+		mockFilename string
+		err          string
 	}
 
 	tests := []struct {
@@ -149,12 +182,100 @@ func TestApply(t *testing.T) {
 			},
 		},
 		{
-			name: "error",
+			name: "hook",
+			args: args{
+				commit: repository.Commit{
+					Hook:        true,
+					MessageFile: "test",
+				},
+			},
+			want: want{
+				mockFilename: "test",
+			},
+		},
+		{
+			name: "hook_summary",
+			args: args{
+				commit: repository.Commit{
+					Subject: "summary",
+					Hook:    true,
+				},
+			},
+			want: want{
+				data: "summary",
+			},
+		},
+		{
+			name: "hook_summary_body",
+			args: args{
+				commit: repository.Commit{
+					Subject: "summary",
+					Body:    "body",
+					Hook:    true,
+				},
+			},
+			want: want{
+				data: "summary\n\nbody",
+			},
+		},
+		{
+			name: "hook_summary_footer",
+			args: args{
+				commit: repository.Commit{
+					Subject: "summary",
+					Footer:  "Signed-off-by: John Doe <[email protected]>",
+					Hook:    true,
+				},
+			},
+			want: want{
+				data: "summary\n\nSigned-off-by: John Doe <[email protected]>",
+			},
+		},
+		{
+			name: "hook_summary_body_footer",
+			args: args{
+				commit: repository.Commit{
+					Subject: "summary",
+					Body:    "body",
+					Footer:  "Signed-off-by: John Doe <[email protected]>",
+					Hook:    true,
+				},
+			},
+			want: want{
+				data: "summary\n\nbody\n\nSigned-off-by: John Doe <[email protected]>",
+			},
+		},
+		{
+			name: "run_error",
+			args: args{
+				runErr: errMock,
+			},
+			want: want{
+				err: "unable to run command: error",
+			},
+		},
+		{
+			name: "hook_error",
+			args: args{
+				commit: repository.Commit{
+					Hook: true,
+				},
+				openFileErr: errMock,
+			},
+			want: want{
+				err: "unble to open file: error",
+			},
+		},
+		{
+			name: "hook_error_close",
 			args: args{
-				err: errMock,
+				commit: repository.Commit{
+					Hook: true,
+				},
+				close: true,
 			},
 			want: want{
-				err: errMock,
+				err: "unable to write file: unable to close file: close",
 			},
 		},
 	}
@@ -165,23 +286,37 @@ func TestApply(t *testing.T) {
 		t.Run(tt.name, func(t *testing.T) {
 			t.Parallel()
 
-			var repo repository.Repository
-
 			shell := MockShell{
-				err: tt.want.err,
+				err: tt.args.runErr,
 			}
 
-			repo.Runner = shell.Run()
+			openFile := MockOpenFile{
+				filename: tt.args.filename,
+				err:      tt.args.openFileErr,
+				close:    tt.args.close,
+			}
+
+			repo := repository.Repository{
+				Runner:    shell.Run(),
+				OpenFiler: openFile.OpenFile(),
+			}
 
 			err := repo.Apply(tt.args.commit)
-			if tt.want.err != nil {
+			if tt.want.err != "" {
 				assert.NotNil(t, err)
-				assert.ErrorContains(t, err, tt.want.err.Error())
+				assert.ErrorContains(t, err, tt.want.err)
 				return
 			}
 			assert.Nil(t, err)
+
 			assert.Equal(t, tt.want.cmd, shell.command)
 			assert.Equal(t, tt.want.args, shell.args)
+
+			if tt.args.commit.Hook {
+				out, _ := os.ReadFile(openFile.mockFilename)
+				assert.Equal(t, tt.want.mockFilename, openFile.filename)
+				assert.Equal(t, tt.want.data, strings.TrimSpace(string(out)))
+			}
 		})
 	}
 }

internal/repository/repository.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"os"
 
 	"github.com/go-git/go-git/v5"
 	"github.com/go-git/go-git/v5/config"
@@ -40,6 +41,7 @@ type Worktreer interface {
 type Repository struct {
 	Opener       func(string, *git.PlainOpenOptions) (*git.Repository, error)
 	Runner       func(io.Writer, string, []string) error
+	OpenFiler    func(string, int, os.FileMode) (*os.File, error)
 	GlobalConfig func(config.Scope) (*config.Config, error)
 	Configer     Configer
 	Remoter      Remoter
@@ -62,6 +64,7 @@ func New() *Repository {
 	return &Repository{
 		GlobalConfig: config.LoadConfig,
 		Opener:       git.PlainOpenWithOptions,
+		OpenFiler:    os.OpenFile,
 		Runner:       shell.Run,
 	}
 }