Display three-way-diff content for text files (#896)

Author: navn-r

jupyterlab_git/git.py

@@ -1173,38 +1173,6 @@ async def _get_tag(self, path, commit_sha):
                 )
             )
 
-    async def show_from_object(self, ref, path):
-        """
-        Execute git show <ref> command & return the result.
-        """
-        command = ["git", "show", ref]
-
-        code, output, error = await execute(command, cwd=path)
-
-        error_messages = map(
-            lambda n: n.lower(),
-            [
-                "fatal: Object '{}' exists on disk, but not here".format(ref),
-                "fatal: Object '{}' does not exist (neither on disk nor in the index)".format(
-                    ref
-                ),
-                # TODO fix this
-                "fatal: Object '{}' does not exist in 'HEAD'".format(ref),
-                "fatal: Invalid object name 'HEAD'",
-            ],
-        )
-        lower_error = error.lower()
-        if code == 0:
-            return output
-        elif any([msg in lower_error for msg in error_messages]):
-            return ""
-        else:
-            raise tornado.web.HTTPError(
-                log_message="Error [{}] occurred while executing [{}] command to retrieve plaintext diff.".format(
-                    error, " ".join(command)
-                )
-            )
-
     async def show(self, filename, ref, path):
         """
         Execute git show <ref:filename> command & return the result.
@@ -1480,32 +1448,3 @@ async def tag_checkout(self, path, tag):
                 "command": " ".join(command),
                 "message": error,
             }
-
-    async def get_unmerged_file_contents(self, filename, path):
-        """
-        Returns the three-way-diff contents of an unmerged file
-
-        Execute `git ls-files -uz <filename>` command & return the file contents
-        Of the three object refs.
-
-        Args:
-            filename (str): Filename (relative to the git repository)
-            path (str): Git repository filepath
-        """
-        command = ["git", "ls-files", "-u", "-z", filename]
-
-        code, output, error = await execute(command, cwd=path)
-        if code != 0:
-            return {
-                "code": code,
-                "command": " ".join(command),
-                "message": error,
-            }
-
-        result = []
-        line_iterable = iter(strip_and_split(output))
-        for line in line_iterable:
-            ref = line.split(" ")[1]
-            content = await self.show_from_object(ref, path)
-            result.append(content)
-        return {"code": code, "contents": result}

jupyterlab_git/handlers.py

@@ -805,22 +805,6 @@ async def post(self, path: str = ""):
         self.finish(json.dumps(result))
 
 
-class GitMergeDiffHandler(GitHandler):
-    """
-    Handler to show a 3-way diff of a file with merge conflicts.
-    """
-
-    @tornado.web.authenticated
-    async def post(self, path: str = ""):
-        data = self.get_json_body()
-        filename = data["filename"]
-        response = await self.git.get_unmerged_file_contents(
-            filename,
-            self.url2localpath(path),
-        )
-        self.finish(json.dumps(response))
-
-
 def setup_handlers(web_app):
     """
     Setups all of the git command handlers.
@@ -858,7 +842,6 @@ def setup_handlers(web_app):
         ("/tags", GitTagHandler),
         ("/tag_checkout", GitTagCheckoutHandler),
         ("/add", GitAddHandler),
-        ("/merge_diff", GitMergeDiffHandler),
     ]
 
     handlers = [

src/commandsAndMenu.tsx

@@ -21,8 +21,9 @@ import { PromiseDelegate } from '@lumino/coreutils';
 import { Message } from '@lumino/messaging';
 import { ContextMenu, Menu, Panel } from '@lumino/widgets';
 import * as React from 'react';
-import { DiffModel } from './components/diff/model';
+import { DiffModel, MergeDiffModel } from './components/diff/model';
 import { createPlainTextDiff } from './components/diff/PlainTextDiff';
+import { createPlainTextMergeDiff } from './components/diff/PlainTextMergeDiff';
 import { CONTEXT_COMMANDS } from './components/FileList';
 import { AUTH_ERROR_MESSAGES, requestAPI } from './git';
 import { logger } from './logger';
@@ -421,6 +422,7 @@ export function addCommands(
    *
    * @params model {Git.Diff.IModel<string>}: The diff model to display
    * @params isText {boolean}: Optional, whether the content is a plain text
+   * @params isMerge {boolean}: Optional, whether the diff is a merge conflict
    * @returns the main area widget or null
    */
   commands.addCommand(CommandIDs.gitShowDiff, {
@@ -433,7 +435,8 @@ export function addCommands(
       };
 
       const buildDiffWidget =
-        getDiffProvider(model.filename) ?? (isText && createPlainTextDiff);
+        getDiffProvider(model.filename) ??
+        (isText && model.base ? createPlainTextMergeDiff : createPlainTextDiff);
 
       if (buildDiffWidget) {
         const id = `diff-${model.filename}-${model.reference.label}-${model.challenger.label}`;
@@ -569,33 +572,29 @@ export function addCommands(
 
         const repositoryPath = gitModel.getRelativeFilePath();
         const filename = PathExt.join(repositoryPath, filePath);
-
-        // Merge conflict
-        if (status === 'unmerged') {
-          const t = await gitModel.getMergeDiff(filename);
-          // TODO: handle
-          console.log(t);
-          continue;
-        }
-
-        let diffContext = context;
-        if (!diffContext) {
-          const specialRef =
-            status === 'staged'
-              ? Git.Diff.SpecialRef.INDEX
-              : Git.Diff.SpecialRef.WORKING;
-          diffContext = {
-            currentRef: specialRef,
-            previousRef: 'HEAD'
-          };
-        }
+        const specialRef =
+          status === 'staged'
+            ? Git.Diff.SpecialRef.INDEX
+            : Git.Diff.SpecialRef.WORKING;
+
+        const diffContext: Git.Diff.IContext =
+          status === 'unmerged'
+            ? {
+                currentRef: 'MERGE_HEAD',
+                previousRef: 'HEAD',
+                baseRef: 'ORIG_HEAD'
+              }
+            : context ?? {
+                currentRef: specialRef,
+                previousRef: 'HEAD'
+              };
 
         const challengerRef = Git.Diff.SpecialRef[diffContext.currentRef as any]
           ? { special: Git.Diff.SpecialRef[diffContext.currentRef as any] }
           : { git: diffContext.currentRef };
 
-        // Create the diff widget
-        const model = new DiffModel<string>({
+        // Base props used for Diff Model
+        const props = {
           challenger: {
             content: async () => {
               return requestAPI<Git.IDiffContent>(
@@ -630,8 +629,32 @@ export function addCommands(
               diffContext.previousRef,
             source: diffContext.previousRef,
             updateAt: Date.now()
+          },
+          // Only add base when diff-ing merge conflicts
+          base: diffContext.baseRef && {
+            content: async () => {
+              return requestAPI<Git.IDiffContent>(
+                URLExt.join(repositoryPath, 'content'),
+                'POST',
+                {
+                  filename: filePath,
+                  reference: { git: diffContext.baseRef }
+                }
+              ).then(data => data.content);
+            },
+            label:
+              (Git.Diff.SpecialRef[diffContext.baseRef as any] as any) ||
+              diffContext.baseRef,
+            source: diffContext.baseRef,
+            updateAt: Date.now()
           }
-        });
+        };
+
+        // Create the diff widget
+        const model =
+          status === 'unmerged'
+            ? new MergeDiffModel<string>(props)
+            : new DiffModel<string>(props);
 
         const widget = await commands.execute(CommandIDs.gitShowDiff, {
           model,