Api for validating the syntax without rendering

src/diagrams/example/example.spec.js

@@ -22,15 +22,4 @@ describe('when parsing an info graph it',function() {
 
         ex.parse(str);
     });
-
-    it('should handle an showMessage statement definition', function () {
-        var str = 'info\nshowInfo';
-
-        try{
-            ex.parse(str);
-        }
-        catch(err){
-            console.log('Caught'+err.message);
-        }
-    });
 });

src/diagrams/flowchart/flowRenderer.js

@@ -188,11 +188,7 @@ exports.getClasses = function (text, isDot) {
     parser.yy = graph;
 
     // Parse the graph definition
-    try{
+    parser.parse(text);
-        parser.parse(text);
-    }
-    catch(err){
-    }
 
     var classDefStylesObj = {};
     var classDefStyleStr = '';

src/diagrams/sequenceDiagram/sequenceRenderer.js

@@ -245,13 +245,8 @@ module.exports.setConf = function(cnf){
  */
 module.exports.draw = function (text, id) {
     sq.yy.clear();
-    //console.log(text);
+    sq.parse(text+'\n');
-    try{
-        sq.parse(text+'\n');
-    }
-    catch(err){
 
-    }
     exports.bounds.init();
     var diagram = d3.select('#'+id);
 

src/main.js

@@ -5,7 +5,49 @@ var flowRenderer = require('./diagrams/flowchart/flowRenderer');
 var seq = require('./diagrams/sequenceDiagram/sequenceRenderer');
 var info = require('./diagrams/example/exampleRenderer');
 var he = require('he');
+var infoParser = require('./diagrams/example/parser/example');
+var flowParser = require('./diagrams/flowchart/parser/flow');
+var dotParser = require('./diagrams/flowchart/parser/dot');
+var sequenceParser = require('./diagrams/sequenceDiagram/parser/sequenceDiagram');
+var sequenceDb = require('./diagrams/sequenceDiagram/sequenceDb');
+var infoDb = require('./diagrams/example/exampleDb');
 
+/**
+ * Function that parses a mermaid diagram defintion. If parsing fails the parseError callback is called and an error is
+ * thrown and
+ * @param text
+ */
+var parse = function(text){
+    var graphType = utils.detectType(text);
+    var parser;
+
+    switch(graphType){
+        case 'graph':
+            parser = flowParser;
+            parser.parser.yy = graph;
+            break;
+        case 'dotGraph':
+            parser = dotParser;
+            parser.parser.yy = graph;
+            break;
+        case 'sequenceDiagram':
+            parser = sequenceParser;
+            parser.parser.yy = sequenceDb;
+            break;
+        case 'info':
+            parser = infoParser;
+            parser.parser.yy = infoDb;
+            break;
+    }
+
+    try{
+        parser.parse(text);
+        return true;
+    }
+    catch(err){
+        return false;
+    }
+};
 /**
  * Function that goes through the document to find the chart definitions in there and render them.
  *
@@ -113,6 +155,9 @@ global.mermaid = {
     getParser:function(){
         return flow.parser;
     },
+    parse:function(text){
+        return parse(text);
+    },
     parseError:function(err,hash){
         console.log('Mermaid Syntax error:');
         console.log(err);

src/main.spec.js

@@ -174,4 +174,88 @@ describe('when using main and ',function() {
             flowRend.addEdges(edges,mockG);
         });
     });
+
+    describe('checking validity of input ', function(){
+        it('it should return false for an invalid definiton',function(){
+            spyOn(mermaid,'parseError');
+            var res = mermaid.parse('this is not a mermaid diagram definition');
+
+            expect(res).toBe(false);
+            expect(mermaid.parseError).toHaveBeenCalled();
+        });
+
+        it('it should return true for a valid flow definition',function(){
+            spyOn(mermaid,'parseError');
+            var res = mermaid.parse('graph TD;A--x|text including URL space|B;');
+
+            expect(res).toBe(true);
+            expect(mermaid.parseError).not.toHaveBeenCalled();
+        });
+        it('it should return false for an invalid flow definition',function(){
+            spyOn(mermaid,'parseError');
+            var res = mermaid.parse('graph TQ;A--x|text including URL space|B;');
+
+            expect(res).toBe(false);
+            expect(mermaid.parseError).toHaveBeenCalled();
+        });
+
+        it('it should return true for a valid sequenceDiagram definition',function(){
+            spyOn(mermaid,'parseError');
+            var str = 'sequenceDiagram\n' +
+                'Alice->Bob: Hello Bob, how are you?\n\n' +
+                '%% Comment\n' +
+                'Note right of Bob: Bob thinks\n' +
+                'alt isWell\n\n' +
+                'Bob-->Alice: I am good thanks!\n' +
+                'else isSick\n' +
+                'Bob-->Alice: Feel sick...\n' +
+                'end';
+            var res = mermaid.parse(str);
+
+            expect(res).toBe(true);
+            expect(mermaid.parseError).not.toHaveBeenCalled();
+        });
+
+        it('it should return false for an invalid sequenceDiagram definition',function(){
+            spyOn(mermaid,'parseError');
+            var str = 'sequenceDiagram\n' +
+                'Alice:->Bob: Hello Bob, how are you?\n\n' +
+                '%% Comment\n' +
+                'Note right of Bob: Bob thinks\n' +
+                'alt isWell\n\n' +
+                'Bob-->Alice: I am good thanks!\n' +
+                'else isSick\n' +
+                'Bob-->Alice: Feel sick...\n' +
+                'end';
+            var res = mermaid.parse(str);
+
+            expect(res).toBe(false);
+            expect(mermaid.parseError).toHaveBeenCalled();
+        });
+
+        it('it should return true for a valid dot definition',function(){
+            spyOn(mermaid,'parseError');
+            var res = mermaid.parse('digraph\n' +
+            '{\n' +
+            ' a -> b -> c -- d -> e;\n' +
+            ' a -- e;\n' +
+            '}');
+
+            expect(res).toBe(true);
+            expect(mermaid.parseError).not.toHaveBeenCalled();
+        });
+        it('it should return false for an invalid dot definition',function(){
+            spyOn(mermaid,'parseError');
+            var res = mermaid.parse('digraph\n' +
+            '{\n' +
+            'a -:> b -> c -- d -> e;\n' +
+            'a -- e;\n' +
+            '}');
+
+            expect(res).toBe(false);
+            expect(mermaid.parseError).toHaveBeenCalled();
+        });
+    });
+
+
 });

src/utils.js

@@ -18,7 +18,7 @@ module.exports.detectType = function(text,a){
     }
 
     if(text.match(/^\s*digraph/)) {
-        console.log('Detected dot syntax');
+        //console.log('Detected dot syntax');
         return "dotGraph";
     }