Implement "until" keyword in gantt charts

cypress/integration/rendering/gantt.spec.js

@@ -14,18 +14,18 @@ describe('Gantt diagram', () => {
       excludes weekdays 2014-01-10
 
       section A section
-      Completed task            :done,    des1, 2014-01-06,2014-01-08
-      Active task               :active,  des2, 2014-01-09, 3d
-      Future task               :         des3, after des2, 5d
-      Future task2               :         des4, after des3, 5d
+      Completed task                      :done, des1, 2014-01-06,2014-01-08
+      Active task                         :active, des2, 2014-01-09, 3d
+      Future task                         :des3, after des2, 5d
+      Future task2                        :des4, after des3, 5d
+      Waiting for task 2                  :after des1, until des4
 
       section Critical tasks
       Completed task in the critical line :crit, done, 2014-01-06,24h
-      Implement parser and jison :crit, done, after des1, 2d
+      Implement parser and jison          :crit, done, after des1, 2d
       Create tests for parser             :crit, active, 3d
       Future task in critical line        :crit, 5d
       Create tests for renderer           :2d
-      Add to mermaid                      :1d
 
       section Documentation
       Describe gantt syntax               :active, a1, after des1, 3d
@@ -88,6 +88,7 @@ describe('Gantt diagram', () => {
       apple :a, 2017-07-20, 1w
       banana :crit, b, 2017-07-23, 1d
       cherry :active, c, after b a, 1d
+      kiwi   :d, 2017-07-20, until b c
       `,
       {}
     );

docs/syntax/gantt.md

@@ -67,8 +67,8 @@ gantt
     Create tests for parser             :crit, active, 3d
     Future task in critical line        :crit, 5d
     Create tests for renderer           :2d
-    Add to mermaid                      :1d
-    Functionality added                 :milestone, 2014-01-25, 0d
+    Add to mermaid                      :until isadded
+    Functionality added                 :milestone, isadded, 2014-01-25, 0d
 
     section Documentation
     Describe gantt syntax               :active, a1, after des1, 3d
@@ -100,8 +100,8 @@ gantt
     Create tests for parser             :crit, active, 3d
     Future task in critical line        :crit, 5d
     Create tests for renderer           :2d
-    Add to mermaid                      :1d
-    Functionality added                 :milestone, 2014-01-25, 0d
+    Add to mermaid                      :until isadded
+    Functionality added                 :milestone, isadded, 2014-01-25, 0d
 
     section Documentation
     Describe gantt syntax               :active, a1, after des1, 3d
@@ -124,18 +124,26 @@ After processing the tags, the remaining metadata items are interpreted as follo
 2.  If two items are specified, the last item is interpreted as in the previous case. The first item can either specify an explicit start date/time (in the format specified by `dateFormat`) or reference another task using `after <otherTaskID> [[otherTaskID2 [otherTaskID3]]...]`. In the latter case, the start date of the task will be set according to the latest end date of any referenced task.
 3.  If three items are specified, the last two will be interpreted as in the previous case. The first item will denote the ID of the task, which can be referenced using the `later <taskID>` syntax.
 
-| Metadata syntax                            | Start date                                          | End date                                    | ID       |
-| ------------------------------------------ | --------------------------------------------------- | ------------------------------------------- | -------- |
-| `<taskID>, <startDate>, <endDate>`         | `startdate` as interpreted using `dateformat`       | `endDate` as interpreted using `dateformat` | `taskID` |
-| `<taskID>, <startDate>, <length>`          | `startdate` as interpreted using `dateformat`       | Start date + `length`                       | `taskID` |
-| `<taskID>, after <otherTaskId>, <endDate>` | End date of previously specified task `otherTaskID` | `endDate` as interpreted using `dateformat` | `taskID` |
-| `<taskID>, after <otherTaskId>, <length>`  | End date of previously specified task `otherTaskID` | Start date + `length`                       | `taskID` |
-| `<startDate>, <endDate>`                   | `startdate` as interpreted using `dateformat`       | `enddate` as interpreted using `dateformat` | n/a      |
-| `<startDate>, <length>`                    | `startdate` as interpreted using `dateformat`       | Start date + `length`                       | n/a      |
-| `after <otherTaskID>, <endDate>`           | End date of previously specified task `otherTaskID` | `enddate` as interpreted using `dateformat` | n/a      |
-| `after <otherTaskID>, <length>`            | End date of previously specified task `otherTaskID` | Start date + `length`                       | n/a      |
-| `<endDate>`                                | End date of preceding task                          | `enddate` as interpreted using `dateformat` | n/a      |
-| `<length>`                                 | End date of preceding task                          | Start date + `length`                       | n/a      |
+| Metadata syntax                                      | Start date                                          | End date                                              | ID       |
+| ---------------------------------------------------- | --------------------------------------------------- | ----------------------------------------------------- | -------- |
+| `<taskID>, <startDate>, <endDate>`                   | `startdate` as interpreted using `dateformat`       | `endDate` as interpreted using `dateformat`           | `taskID` |
+| `<taskID>, <startDate>, <length>`                    | `startdate` as interpreted using `dateformat`       | Start date + `length`                                 | `taskID` |
+| `<taskID>, after <otherTaskId>, <endDate>`           | End date of previously specified task `otherTaskID` | `endDate` as interpreted using `dateformat`           | `taskID` |
+| `<taskID>, after <otherTaskId>, <length>`            | End date of previously specified task `otherTaskID` | Start date + `length`                                 | `taskID` |
+| `<taskID>, <startDate>, until <otherTaskId>`         | `startdate` as interpreted using `dateformat`       | Start date of previously specified task `otherTaskID` | `taskID` |
+| `<taskID>, after <otherTaskId>, until <otherTaskId>` | End date of previously specified task `otherTaskID` | Start date of previously specified task `otherTaskID` | `taskID` |
+| `<startDate>, <endDate>`                             | `startdate` as interpreted using `dateformat`       | `enddate` as interpreted using `dateformat`           | n/a      |
+| `<startDate>, <length>`                              | `startdate` as interpreted using `dateformat`       | Start date + `length`                                 | n/a      |
+| `after <otherTaskID>, <endDate>`                     | End date of previously specified task `otherTaskID` | `enddate` as interpreted using `dateformat`           | n/a      |
+| `after <otherTaskID>, <length>`                      | End date of previously specified task `otherTaskID` | Start date + `length`                                 | n/a      |
+| `<startDate>, until <otherTaskId>`                   | `startdate` as interpreted using `dateformat`       | Start date of previously specified task `otherTaskID` | n/a      |
+| `after <otherTaskId>, until <otherTaskId>`           | End date of previously specified task `otherTaskID` | Start date of previously specified task `otherTaskID` | n/a      |
+| `<endDate>`                                          | End date of preceding task                          | `enddate` as interpreted using `dateformat`           | n/a      |
+| `<length>`                                           | End date of preceding task                          | Start date + `length`                                 | n/a      |
+| `until <otherTqskId>`                                | End date of preceding task                          | Start date of previously specified task `otherTaskID` | n/a      |
+
+> **Note**
+> Support for keyword `until` was added in (v\<MERMAID_RELEASE_VERSION>+). This can be used to define a task which is running until some other specific task or milestone starts.
 
 For simplicity, the table does not show the use of multiple tasks listed with the `after` keyword. Here is an example of how to use it and how it's interpreted:
 
@@ -144,13 +152,15 @@ gantt
     apple :a, 2017-07-20, 1w
     banana :crit, b, 2017-07-23, 1d
     cherry :active, c, after b a, 1d
+    kiwi   :d, 2017-07-20, until b c
 ```
 
 ```mermaid
 gantt
     apple :a, 2017-07-20, 1w
     banana :crit, b, 2017-07-23, 1d
     cherry :active, c, after b a, 1d
+    kiwi   :d, 2017-07-20, until b c
 ```
 
 ### Title

packages/mermaid/src/diagrams/gantt/ganttDb.js

@@ -256,31 +256,25 @@
   str = str.trim();
 
   // Test for after
-  const re = /^after\s+([\d\w- ]+)/;
-  const afterStatement = re.exec(str.trim());
+  const afterRePattern = /^after\s+(?<ids>[\d\w- ]+)/;
+  const afterStatement = afterRePattern.exec(str);
 
   if (afterStatement !== null) {
     // check all after ids and take the latest
-    let latestEndingTask = null;
-    afterStatement[1].split(' ').forEach(function (id) {
+    let latestTask = null;
+    for (const id of afterStatement.groups.ids.split(' ')) {
       let task = findTaskById(id);
-      if (task !== undefined) {
-        if (!latestEndingTask) {
-          latestEndingTask = task;
-        } else {
-          if (task.endTime > latestEndingTask.endTime) {
-            latestEndingTask = task;
-          }
-        }
+      if (task !== undefined && (!latestTask || task.endTime > latestTask.endTime)) {
+        latestTask = task;
       }
-    });
+    }
 
-    if (!latestEndingTask) {
-      const dt = new Date();
-      dt.setHours(0, 0, 0, 0);
-      return dt;
+    if (latestTask) {
+      return latestTask.endTime;
     } else {
-      return latestEndingTask.endTime;
+      const today = new Date();
+      today.setHours(0, 0, 0, 0);
+      return today;
     }
   }
 
@@ -343,13 +337,36 @@
 const getEndDate = function (prevTime, dateFormat, str, inclusive = false) {
   str = str.trim();
 
-  // Check for actual date
-  let mDate = dayjs(str, dateFormat.trim(), true);
-  if (mDate.isValid()) {
+  // test for until
+  const untilRePattern = /^until\s+(?<ids>[\d\w- ]+)/;
+  const untilStatement = untilRePattern.exec(str);
+
+  if (untilStatement !== null) {
+    // check all until ids and take the earliest
+    let earliestTask = null;
+    for (const id of untilStatement.groups.ids.split(' ')) {
+      let task = findTaskById(id);
+      if (task !== undefined && (!earliestTask || task.startTime < earliestTask.startTime)) {
+        earliestTask = task;
+      }
+    }
+
+    if (earliestTask) {
+      return earliestTask.startTime;
+    } else {
+      const today = new Date();
+      today.setHours(0, 0, 0, 0);
+      return today;
+    }
+  }
+
+  // check for actual date
+  let parsedDate = dayjs(str, dateFormat.trim(), true);
+  if (parsedDate.isValid()) {
     if (inclusive) {
-      mDate = mDate.add(1, 'd');
+      parsedDate = parsedDate.add(1, 'd');
     }
-    return mDate.toDate();
+    return parsedDate.toDate();
   }
 
   let endTime = dayjs(prevTime);

packages/mermaid/src/diagrams/gantt/ganttDb.spec.ts

@@ -140,10 +140,10 @@ describe('when using the ganttDb', function () {
 
   it('should handle relative start date based on id regardless of sections', function () {
     ganttDb.setDateFormat('YYYY-MM-DD');
-    ganttDb.addSection('testa1');
+    ganttDb.addSection('sec1');
     ganttDb.addTask('test1', 'id1,2013-01-01,2w');
     ganttDb.addTask('test2', 'id2,after id3,1d');
-    ganttDb.addSection('testa2');
+    ganttDb.addSection('sec2');
     ganttDb.addTask('test3', 'id3,after id1,2d');
 
     const tasks = ganttDb.getTasks();
@@ -158,6 +158,58 @@ describe('when using the ganttDb', function () {
     expect(tasks[2].startTime).toEqual(new Date(2013, 0, 15));
     expect(tasks[2].endTime).toEqual(new Date(2013, 0, 17));
   });
+
+  it('should handle relative end date based on id regardless of sections', function () {
+    ganttDb.setDateFormat('YYYY-MM-DD');
+    ganttDb.addSection('sec1');
+    ganttDb.addTask('task1', 'id1,2013-01-01,until id3');
+    ganttDb.addSection('sec2');
+    ganttDb.addTask('task2', 'id2,2013-01-10,until id3');
+    ganttDb.addTask('task3', 'id3,2013-02-01,2d');
+
+    const tasks = ganttDb.getTasks();
+
+    expect(tasks[0].startTime).toEqual(new Date(2013, 0, 1));
+    expect(tasks[0].endTime).toEqual(new Date(2013, 1, 1));
+    expect(tasks[0].id).toEqual('id1');
+    expect(tasks[0].task).toEqual('task1');
+
+    expect(tasks[1].id).toEqual('id2');
+    expect(tasks[1].task).toEqual('task2');
+    expect(tasks[1].startTime).toEqual(new Date(2013, 0, 10));
+    expect(tasks[1].endTime).toEqual(new Date(2013, 1, 1));
+  });
+
+  it('should handle relative start date based on multiple id', function () {
+    ganttDb.setDateFormat('YYYY-MM-DD');
+    ganttDb.addSection('sec1');
+    ganttDb.addTask('task1', 'id1,after id2 id3 id4,1d');
+    ganttDb.addTask('task2', 'id2,2013-01-01,1d');
+    ganttDb.addTask('task3', 'id3,2013-02-01,3d');
+    ganttDb.addTask('task4', 'id4,2013-02-01,2d');
+
+    const tasks = ganttDb.getTasks();
+
+    expect(tasks[0].endTime).toEqual(new Date(2013, 1, 5));
+    expect(tasks[0].id).toEqual('id1');
+    expect(tasks[0].task).toEqual('task1');
+  });
+
+  it('should handle relative end date based on multiple id', function () {
+    ganttDb.setDateFormat('YYYY-MM-DD');
+    ganttDb.addSection('sec1');
+    ganttDb.addTask('task1', 'id1,2013-01-01,until id2 id3 id4');
+    ganttDb.addTask('task2', 'id2,2013-01-11,1d');
+    ganttDb.addTask('task3', 'id3,2013-02-10,1d');
+    ganttDb.addTask('task4', 'id4,2013-02-12,1d');
+
+    const tasks = ganttDb.getTasks();
+
+    expect(tasks[0].endTime).toEqual(new Date(2013, 0, 11));
+    expect(tasks[0].id).toEqual('id1');
+    expect(tasks[0].task).toEqual('task1');
+  });
+
   it('should ignore weekends', function () {
     ganttDb.setDateFormat('YYYY-MM-DD');
     ganttDb.setExcludes('weekends 2019-02-06,friday');

packages/mermaid/src/diagrams/gantt/parser/gantt.spec.js

@@ -118,6 +118,38 @@ describe('when parsing a gantt diagram it', function () {
     expect(tasks[0].id).toEqual('des1');
     expect(tasks[0].task).toEqual('Design jison grammar');
   });
+  it('should handle a task with start/end time relative to other tasks', function () {
+    const str =
+      'gantt\n' +
+      'dateFormat YYYY-MM-DD\n' +
+      'title Adding gantt diagram functionality to mermaid\n' +
+      'section Documentation\n' +
+      'task A: a, 2024-01-27, 2024-01-28\n' +
+      'task B: b, after a, 2024-01-30\n' +
+      'task C: c, 2024-01-20, until a\n' +
+      'task D: d, after c, until b';
+
+    expect(parserFnConstructor(str)).not.toThrow();
+
+    const tasks = parser.yy.getTasks();
+
+    expect(tasks[0].startTime).toEqual(new Date(2024, 0, 27));
+    expect(tasks[0].endTime).toEqual(new Date(2024, 0, 28));
+    expect(tasks[0].id).toEqual('a');
+    expect(tasks[0].task).toEqual('task A');
+    expect(tasks[1].startTime).toEqual(new Date(2024, 0, 28));
+    expect(tasks[1].endTime).toEqual(new Date(2024, 0, 30));
+    expect(tasks[1].id).toEqual('b');
+    expect(tasks[1].task).toEqual('task B');
+    expect(tasks[2].startTime).toEqual(new Date(2024, 0, 20));
+    expect(tasks[2].endTime).toEqual(new Date(2024, 0, 27));
+    expect(tasks[2].id).toEqual('c');
+    expect(tasks[2].task).toEqual('task C');
+    expect(tasks[3].startTime).toEqual(new Date(2024, 0, 27));
+    expect(tasks[3].endTime).toEqual(new Date(2024, 0, 28));
+    expect(tasks[3].id).toEqual('d');
+    expect(tasks[3].task).toEqual('task D');
+  });
   it.each(convert`
     tags                     | milestone | done     | crit     | active
     ${'milestone'}           | ${true}   | ${false} | ${false} | ${false}