From 13d85b6ee5d3569b4e2d675c04ba7d7e8c4a8543 Mon Sep 17 00:00:00 2001
From: RounakJoshi09 <rounakjsh783@gmail.com>
Date: Thu, 12 Oct 2023 02:35:43 +0530
Subject: [PATCH] Parser and Logic For Parent Commit Added

---
 .../mermaid/src/diagrams/git/gitGraphAst.js   | 46 +++++++++++++------
 .../src/diagrams/git/parser/gitGraph.jison    | 10 +++-
 2 files changed, 40 insertions(+), 16 deletions(-)

diff --git a/packages/mermaid/src/diagrams/git/gitGraphAst.js b/packages/mermaid/src/diagrams/git/gitGraphAst.js
index abad68b22b..15e8a3e381 100644
--- a/packages/mermaid/src/diagrams/git/gitGraphAst.js
+++ b/packages/mermaid/src/diagrams/git/gitGraphAst.js
@@ -256,7 +256,7 @@ export const merge = function (otherBranch, custom_id, override_type, custom_tag
   log.debug('in mergeBranch');
 };
 
-export const cherryPick = function (sourceId, targetId, tag) {
+export const cherryPick = function (sourceId, targetId, tag, parentCommit) {
   log.debug('Entering cherryPick:', sourceId, targetId, tag);
   sourceId = common.sanitizeText(sourceId, configApi.getConfig());
   targetId = common.sanitizeText(targetId, configApi.getConfig());
@@ -275,21 +275,35 @@ export const cherryPick = function (sourceId, targetId, tag) {
     };
     throw error;
   }
-
   let sourceCommit = commits[sourceId];
   let sourceCommitBranch = sourceCommit.branch;
   if (sourceCommit.type === commitType.MERGE) {
-    let error = new Error(
-      'Incorrect usage of "cherryPick". Source commit should not be a merge commit'
-    );
-    error.hash = {
-      text: 'cherryPick ' + sourceId + ' ' + targetId,
-      token: 'cherryPick ' + sourceId + ' ' + targetId,
-      line: '1',
-      loc: { first_line: 1, last_line: 1, first_column: 1, last_column: 1 },
-      expected: ['cherry-pick abc'],
-    };
-    throw error;
+    if (!parentCommit) {
+      let error = new Error(
+        'Incorrect usage of cherryPick: If the source commit is a merge commit, an immediate parent commit must be specified.'
+      );
+      error.hash = {
+        text: 'cherryPick ' + sourceId + ' ' + targetId,
+        token: 'cherryPick ' + sourceId + ' ' + targetId,
+        line: '1',
+        loc: { first_line: 1, last_line: 1, first_column: 1, last_column: 1 },
+        expected: ['cherry-pick abc'],
+      };
+      throw error;
+    }
+    if (!(Array.isArray(sourceCommit.parents) && sourceCommit.parents.includes(parentCommit))) {
+      let error = new Error(
+        'Invalid operation: The specified parent commit is not an immediate parent of the cherry-picked commit.'
+      );
+      error.hash = {
+        text: 'cherryPick ' + sourceId + ' ' + targetId,
+        token: 'cherryPick ' + sourceId + ' ' + targetId,
+        line: '1',
+        loc: { first_line: 1, last_line: 1, first_column: 1, last_column: 1 },
+        expected: ['cherry-pick abc'],
+      };
+      throw error;
+    }
   }
   if (!targetId || commits[targetId] === undefined) {
     // cherry-pick source commit to current branch
@@ -328,7 +342,11 @@ export const cherryPick = function (sourceId, targetId, tag) {
       parents: [head == null ? null : head.id, sourceCommit.id],
       branch: curBranch,
       type: commitType.CHERRY_PICK,
-      tag: tag ?? 'cherry-pick:' + sourceCommit.id,
+      tag: tag
+        ? `${tag}${sourceCommit.type === commitType.MERGE ? ` | parent: ${parentCommit}` : ''}`
+        : `cherry-pick: ${sourceCommit.id}${
+            sourceCommit.type === commitType.MERGE ? ` | parent: ${parentCommit}` : ''
+          }`,
     };
     head = commit;
     commits[commit.id] = commit;
diff --git a/packages/mermaid/src/diagrams/git/parser/gitGraph.jison b/packages/mermaid/src/diagrams/git/parser/gitGraph.jison
index 2297db17cd..1e4ca026ed 100644
--- a/packages/mermaid/src/diagrams/git/parser/gitGraph.jison
+++ b/packages/mermaid/src/diagrams/git/parser/gitGraph.jison
@@ -39,6 +39,7 @@ branch(?=\s|$)                          return 'BRANCH';
 "order:"                                return 'ORDER';
 merge(?=\s|$)                           return 'MERGE';
 cherry\-pick(?=\s|$)                    return 'CHERRY_PICK';
+"parent:"                               return 'PARENT_COMMIT'
 // "reset"                                 return 'RESET';
 checkout(?=\s|$)                        return 'CHECKOUT';
 "LR"                                    return 'DIR';
@@ -109,10 +110,15 @@ branchStatement
 
 cherryPickStatement
     : CHERRY_PICK COMMIT_ID STR {yy.cherryPick($3, '', undefined)}
+    | CHERRY_PICK COMMIT_ID STR PARENT_COMMIT STR {yy.cherryPick($3, '', undefined,$5)}
     | CHERRY_PICK COMMIT_ID STR COMMIT_TAG STR {yy.cherryPick($3, '', $5)}
+    | CHERRY_PICK COMMIT_ID STR PARENT_COMMIT STR COMMIT_TAG STR {yy.cherryPick($3, '', $7,$5)}
+    | CHERRY_PICK COMMIT_ID STR COMMIT_TAG STR PARENT_COMMIT STR {yy.cherryPick($3, '', $5,$7)}
     | CHERRY_PICK COMMIT_ID STR COMMIT_TAG EMPTYSTR {yy.cherryPick($3, '', '')}
-    | CHERRY_PICK COMMIT_TAG STR COMMIT_ID STR {yy.cherryPick($5, '', $3)}
-    | CHERRY_PICK COMMIT_TAG EMPTYSTR COMMIT_ID STR {yy.cherryPick($3, '', '')}
+    | CHERRY_PICK COMMIT_ID STR PARENT_COMMIT STR COMMIT_TAG EMPTYSTR {yy.cherryPick($3, '', '',$5)}
+    | CHERRY_PICK COMMIT_ID STR COMMIT_TAG EMPTYSTR PARENT_COMMIT STR {yy.cherryPick($3, '', '',$7)}
+    | CHERRY_PICK COMMIT_TAG STR COMMIT_ID STR PARENT_COMMIT STR {yy.cherryPick($5, '', $3,$7)}
+    | CHERRY_PICK COMMIT_TAG EMPTYSTR COMMIT_ID STR PARENT_COMMIT STR{yy.cherryPick($5, '', '',$7)}
     ;
 
 mergeStatement