Gitgraph: Make reset work with parent ref carets

src/diagrams/gitGraph/gitGraphAst.js

@@ -118,9 +118,21 @@ exports.checkout = function(branch) {
     head = commits[id];
 }
 
-exports.reset = function(ref) {
-    log.debug('in reset');
+exports.reset = function(commitRef) {
+    log.debug('in reset', commitRef);
+    var ref = commitRef.split(':')[0];
+    var parentCount = parseInt(commitRef.split(':')[1]);
     var commit = ref == 'HEAD' ? head : commits[branches[ref]];
+    log.debug(commit, parentCount);
+    while (parentCount > 0) {
+        commit = commits[commit.parent];
+        parentCount--;
+        if (!commit) {
+            var err = 'Critical error - unique parent commit not found during reset';
+            log.error(err);
+            throw err;
+        }
+    }
     head = commit;
     branches[curBranch] = commit.id;
 }

src/diagrams/gitGraph/gitGraphParser.spec.js

@@ -72,7 +72,7 @@ describe('when parsing a gitGraph',function() {
     });
 
     it('should handle set direction', function () {
-        var str = 'gitGraph TB:\n' +
+        var str = 'gitGraph BT:\n' +
         'commit\n';
 
         parser.parse(str);
@@ -81,7 +81,7 @@ describe('when parsing a gitGraph',function() {
 
         expect(Object.keys(commits).length).toBe(1);
         expect(parser.yy.getCurrentBranch()).toBe('master');
-        expect(parser.yy.getDirection()).toBe('TB');
+        expect(parser.yy.getDirection()).toBe('BT');
         expect(Object.keys(parser.yy.getBranches()).length).toBe(1);
     });
 
@@ -145,6 +145,24 @@ describe('when parsing a gitGraph',function() {
         expect(parser.yy.getHead().id).toEqual(parser.yy.getBranches()['newbranch']);
     });
 
+    it('reset can take an argument', function () {
+        var str = 'gitGraph:\n' +
+        'commit\n' +
+        'commit\n' +
+        'branch newbranch\n' +
+        'checkout newbranch\n' +
+        'commit\n' +
+        'reset master^\n';
+
+        parser.parse(str);
+
+        var commits = parser.yy.getCommits();
+        expect(Object.keys(commits).length).toBe(3);
+        expect(parser.yy.getCurrentBranch()).toBe('newbranch');
+        var master = commits[parser.yy.getBranches()['master']];
+        expect(parser.yy.getHead().id).toEqual(master.parent);
+    })
+
     it('it should handle fast forwardable merges', function () {
         var str = 'gitGraph:\n' +
         'commit\n' +

src/diagrams/gitGraph/parser/gitGraph.jison

@@ -25,9 +25,9 @@
 "reset"                         return 'RESET';
 "checkout"                         return 'CHECKOUT';
 "LR"                            return 'DIR';
-"TB"                            return 'DIR';
 "BT"                            return 'DIR';
 ":"                             return ':';
+"^"                             return 'CARET'
 "options"\r?\n                       this.begin("options");
 <options>"end"\r?\n                   this.popState();
 <options>[^\n]+\r?\n                 return 'OPT';
@@ -83,6 +83,10 @@ commit_arg
     ;
 
 reset_arg
-    : 'HEAD' 
-    | ID
+    : 'HEAD' reset_parents{$$ = $1+ ":" + $2 }
+    | ID reset_parents{$$ = $1+ ":"  + yy.count; yy.count = 0}
+    ;
+reset_parents
+    : /* empty */ {yy.count = 0}
+    | CARET reset_parents { yy.count += 1 }
     ;

testgitgraph.mm

@@ -1,6 +1,6 @@
 gitGraph BT:
 options
-{"key": "value",
+{
 "nodeSpacing": 150
 }
 end
@@ -13,4 +13,7 @@
     commit
     commit
     merge newbranch
+    reset newbranch^^
+    commit
+    commit