From 69ce29841d496d2e7acda8c2c7308ba722979222 Mon Sep 17 00:00:00 2001
From: Richard Gibson <richard.gibson@gmail.com>
Date: Sun, 6 Dec 2015 05:51:02 -0500
Subject: [PATCH 1/2] Test for sequenceDiagram participant aliasing

---
 .../sequenceDiagram/sequenceDiagram.spec.js   | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/src/diagrams/sequenceDiagram/sequenceDiagram.spec.js b/src/diagrams/sequenceDiagram/sequenceDiagram.spec.js
index a2922858b3..effabd47e9 100644
--- a/src/diagrams/sequenceDiagram/sequenceDiagram.spec.js
+++ b/src/diagrams/sequenceDiagram/sequenceDiagram.spec.js
@@ -67,6 +67,25 @@ describe('when parsing a sequenceDiagram',function() {
         expect(messages[0].from).toBe('Alice');
         expect(messages[1].from).toBe('Bob');
     });
+    it('it should alias participants', function () {
+        str = 'sequenceDiagram\n' +
+            'participant A as Alice\n' +
+            'participant B as Bob\n' +
+            'A->B:Hello Bob, how are you?\n' +
+            'B-->A: I am good thanks!';
+
+        sq.parse(str);
+
+        var actors = sq.yy.getActors();
+        expect(Object.keys(actors)).toEqual(['A', 'B']);
+        expect(actors.A.description).toBe('Alice');
+        expect(actors.B.description).toBe('Bob');
+
+        var messages = sq.yy.getMessages();
+        expect(messages.length).toBe(2);
+        expect(messages[0].from).toBe('A');
+        expect(messages[1].from).toBe('B');
+    });
     it('it should handle in async messages', function () {
         var str = 'sequenceDiagram\n' +
         'Alice-xBob:Hello Bob, how are you?';

From b42939796c959383ccacf931c1dbc4a0a5dfcfde Mon Sep 17 00:00:00 2001
From: Richard Gibson <richard.gibson@gmail.com>
Date: Sun, 6 Dec 2015 05:53:08 -0500
Subject: [PATCH 2/2] Allow sequenceDiagram participant aliasing

Fixes gh-263
---
 .../parser/sequenceDiagram.jison              | 25 +++++++++++--------
 src/diagrams/sequenceDiagram/sequenceDb.js    | 11 +++++---
 2 files changed, 23 insertions(+), 13 deletions(-)

diff --git a/src/diagrams/sequenceDiagram/parser/sequenceDiagram.jison b/src/diagrams/sequenceDiagram/parser/sequenceDiagram.jison
index 2af34f4ec3..47cbea8e95 100644
--- a/src/diagrams/sequenceDiagram/parser/sequenceDiagram.jison
+++ b/src/diagrams/sequenceDiagram/parser/sequenceDiagram.jison
@@ -12,17 +12,24 @@
 
 %options case-insensitive
 
+// Special states for recognizing aliases
+%x ID
+%x ALIAS
+
 // A special state for grabbing text up to the first comment/newline
 %x LINE
 
 %%
 
-[\n]+                   return 'NL';
-\s+                     /* skip all whitespace */
-<LINE>((?!\n)\s)+       /* skip same-line whitespace */
-<INITIAL,LINE>\#[^\n]*  /* skip comments */
-\%%[^\n]*               /* skip comments */
-"participant"     return 'participant';
+[\n]+                            return 'NL';
+\s+                              /* skip all whitespace */
+<ID,ALIAS,LINE>((?!\n)\s)+       /* skip same-line whitespace */
+<INITIAL,ID,ALIAS,LINE>\#[^\n]*  /* skip comments */
+\%%[^\n]*                        /* skip comments */
+"participant"     { this.begin('ID'); return 'participant'; }
+<ID>[^\->:\n,;]+?(?=((?!\n)\s)+"as"(?!\n)\s|[#\n;]|$)  { this.begin('ALIAS'); return 'ACTOR'; }
+<ALIAS>"as"       { this.popState(); this.popState(); this.begin('LINE'); return 'AS'; }
+<ALIAS>(?:)       { this.popState(); this.popState(); return 'NL'; }
 "loop"            { this.begin('LINE'); return 'loop'; }
 "opt"             { this.begin('LINE'); return 'opt'; }
 "alt"             { this.begin('LINE'); return 'alt'; }
@@ -72,7 +79,8 @@ line
 	;
 
 statement
-	: 'participant' actor 'NL' {$$=$2;}
+	: 'participant' actor 'AS' restOfLine 'NL' {$2.description=$4; $$=$2;}
+	| 'participant' actor 'NL' {$$=$2;}
 	| signal 'NL'
 	| note_statement 'NL'
 	| 'title' SPACE text 'NL'
@@ -133,9 +141,6 @@ signal
 	{$$ = [$1,$3,{type: 'addMessage', from:$1.actor, to:$3.actor, signalType:$2, msg:$4}]}
 	;
 
-actors: actors actor
-	  | actor
-	  ;
 actor
 	: ACTOR {$$={type: 'addActor', actor:$1}}
 	;
diff --git a/src/diagrams/sequenceDiagram/sequenceDb.js b/src/diagrams/sequenceDiagram/sequenceDb.js
index 284315bd0a..e924bd6845 100644
--- a/src/diagrams/sequenceDiagram/sequenceDb.js
+++ b/src/diagrams/sequenceDiagram/sequenceDb.js
@@ -2,7 +2,6 @@
  * Created by knut on 14-11-19.
  */
 var actors    = {};
-var actorKeys = [];
 var messages  = [];
 var notes     = [];
 var Logger = require('../../logger');
@@ -11,8 +10,14 @@ var log = new Logger.Log();
 
 
 exports.addActor = function(id,name,description){
+    // Don't allow description nulling
+    var old = actors[id];
+    if ( old && name === old.name && description == null ) return;
+
+    // Don't allow null descriptions, either
+    if ( description == null ) description = name;
+
     actors[id] = {name:name, description:description};
-    actorKeys.push(id);
 };
 
 exports.addMessage = function(idFrom, idTo, message,  answer){
@@ -98,7 +103,7 @@ exports.apply = function(param){
         // log.debug(param);
         switch(param.type){
             case 'addActor':
-                exports.addActor(param.actor, param.actor, param.actor);
+                exports.addActor(param.actor, param.actor, param.description);
                 break;
             case 'addNote':
                 exports.addNote(param.actor,param.placement, param.text);