Add commands for reviews (#315)

add interactive `tea pr review`

it's amazingly simple

vendor gitea.com/noerw/unidiff-comments

add `tea pr lgtm|reject` shorthands

vendor slimmed down diff parser

review diff: default to true

if users want a shortcut, they can use lgtm or reject subcmds

`tea pr approve`: accept optional comment

Co-authored-by: Norwin Roosen <git@nroo.de>
Reviewed-on: https://gitea.com/gitea/tea/pulls/315
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Reviewed-by: 6543 <6543@obermui.de>
Co-Authored-By: Norwin <noerw@noreply.gitea.io>
Co-Committed-By: Norwin <noerw@noreply.gitea.io>

modules/task/pull_review.go

@@ -0,0 +1,128 @@
+// Copyright 2020 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package task
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"strings"
+
+	"code.gitea.io/tea/modules/context"
+
+	"code.gitea.io/sdk/gitea"
+	unidiff "gitea.com/noerw/unidiff-comments"
+)
+
+var diffReviewHelp = `# This is the current diff of PR #%d on %s.
+# To add code comments, just insert a line inside the diff with your comment,
+# prefixed with '# '. For example:
+#
+# - foo: string,
+# - bar: string,
+# + foo: int,
+# # This is a code comment
+# + bar: int,
+
+`
+
+// CreatePullReview submits a review for a PR
+func CreatePullReview(ctx *context.TeaContext, idx int64, status gitea.ReviewStateType, comment string, codeComments []gitea.CreatePullReviewComment) error {
+	c := ctx.Login.Client()
+
+	review, _, err := c.CreatePullReview(ctx.Owner, ctx.Repo, idx, gitea.CreatePullReviewOptions{
+		State:    status,
+		Body:     comment,
+		Comments: codeComments,
+	})
+	if err != nil {
+		return err
+	}
+
+	fmt.Println(review.HTMLURL)
+	return nil
+}
+
+// SavePullDiff fetches the diff of a pull request and stores it as a temporary file.
+// The path to the file is returned.
+func SavePullDiff(ctx *context.TeaContext, idx int64) (string, error) {
+	diff, _, err := ctx.Login.Client().GetPullRequestDiff(ctx.Owner, ctx.Repo, idx)
+	if err != nil {
+		return "", err
+	}
+	writer, err := ioutil.TempFile(os.TempDir(), fmt.Sprintf("pull-%d-review-*.diff", idx))
+	if err != nil {
+		return "", err
+	}
+	defer writer.Close()
+
+	// add a help header before the actual diff
+	if _, err = fmt.Fprintf(writer, diffReviewHelp, idx, ctx.RepoSlug); err != nil {
+		return "", err
+	}
+
+	if _, err = writer.Write(diff); err != nil {
+		return "", err
+	}
+	return writer.Name(), nil
+}
+
+// ParseDiffComments reads a diff, extracts comments from it & returns them in a gitea compatible struct
+func ParseDiffComments(diffFile string) ([]gitea.CreatePullReviewComment, error) {
+	reader, err := os.Open(diffFile)
+	if err != nil {
+		return nil, fmt.Errorf("couldn't load diff: %s", err)
+	}
+	defer reader.Close()
+
+	changeset, err := unidiff.ReadChangeset(reader)
+	if err != nil {
+		return nil, fmt.Errorf("couldn't parse patch: %s", err)
+	}
+
+	var comments []gitea.CreatePullReviewComment
+	for _, file := range changeset.Diffs {
+		for _, c := range file.LineComments {
+			comment := gitea.CreatePullReviewComment{
+				Body: c.Text,
+				Path: c.Anchor.Path,
+			}
+			comment.Path = strings.TrimPrefix(comment.Path, "a/")
+			comment.Path = strings.TrimPrefix(comment.Path, "b/")
+			switch c.Anchor.LineType {
+			case "ADDED":
+				comment.NewLineNum = c.Anchor.Line
+			case "REMOVED", "CONTEXT":
+				comment.OldLineNum = c.Anchor.Line
+			}
+			comments = append(comments, comment)
+		}
+	}
+
+	return comments, nil
+}
+
+// OpenFileInEditor opens filename in a text editor, and blocks until the editor terminates.
+func OpenFileInEditor(filename string) error {
+	editor := os.Getenv("EDITOR")
+	if editor == "" {
+		fmt.Println("No $EDITOR env is set, defaulting to vim")
+		editor = "vim"
+	}
+
+	// Get the full executable path for the editor.
+	executable, err := exec.LookPath(editor)
+	if err != nil {
+		return err
+	}
+
+	cmd := exec.Command(executable, filename)
+	cmd.Stdin = os.Stdin
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+
+	return cmd.Run()
+}