Include line info in compiler thrown exceptions

Fixes #636

Author: kpdecker

lib/handlebars/base.js

@@ -53,7 +53,7 @@ function registerDefaultHelpers(instance) {
     if(arguments.length === 2) {
       return undefined;
     } else {
-      throw new Error("Missing helper: '" + arg + "'");
+      throw new Exception("Missing helper: '" + arg + "'");
     }
   });
 

lib/handlebars/compiler/ast.js

@@ -106,12 +106,12 @@ var AST = {
   },
 
   BlockNode: function(mustache, program, inverse, close, locInfo) {
+    LocationInfo.call(this, locInfo);
+
     if(mustache.sexpr.id.original !== close.path.original) {
-      throw new Exception(mustache.sexpr.id.original + " doesn't match " + close.path.original);
+      throw new Exception(mustache.sexpr.id.original + " doesn't match " + close.path.original, this);
     }
 
-    LocationInfo.call(this, locInfo);
-
     this.type = 'block';
     this.mustache = mustache;
     this.program  = program;
@@ -155,11 +155,16 @@ var AST = {
       original += (parts[i].separator || '') + part;
 
       if (part === ".." || part === "." || part === "this") {
-        if (dig.length > 0) { throw new Exception("Invalid path: " + original); }
-        else if (part === "..") { depth++; }
-        else { this.isScoped = true; }
+        if (dig.length > 0) {
+          throw new Exception("Invalid path: " + original, this);
+        } else if (part === "..") {
+          depth++;
+        } else {
+          this.isScoped = true;
+        }
+      } else {
+        dig.push(part);
       }
-      else { dig.push(part); }
     }
 
     this.original = original;

lib/handlebars/compiler/compiler.js

@@ -279,7 +279,7 @@ Compiler.prototype = {
     if (this.options.knownHelpers[name]) {
       this.opcode('invokeKnownHelper', params.length, name);
     } else if (this.options.knownHelpersOnly) {
-      throw new Error("You specified knownHelpersOnly, but used the unknown helper " + name);
+      throw new Exception("You specified knownHelpersOnly, but used the unknown helper " + name, sexpr);
     } else {
       this.opcode('invokeHelper', params.length, name, sexpr.isRoot);
     }
@@ -316,7 +316,7 @@ Compiler.prototype = {
   DATA: function(data) {
     this.options.data = true;
     if (data.id.isScoped || data.id.depth) {
-      throw new Exception('Scoped data references are not supported: ' + data.original);
+      throw new Exception('Scoped data references are not supported: ' + data.original, data);
     }
 
     this.opcode('lookupData');
@@ -350,7 +350,6 @@ Compiler.prototype = {
   },
 
   addDepth: function(depth) {
-    if(isNaN(depth)) { throw new Error("EWOT"); }
     if(depth === 0) { return; }
 
     if(!this.depths[depth]) {

lib/handlebars/exception.js

@@ -1,13 +1,25 @@
 
 var errorProps = ['description', 'fileName', 'lineNumber', 'message', 'name', 'number', 'stack'];
 
-function Exception(/* message */) {
-  var tmp = Error.prototype.constructor.apply(this, arguments);
+function Exception(message, node) {
+  var line;
+  if (node && node.firstLine) {
+    line = node.firstLine;
+
+    message += ' - ' + line + ':' + node.firstColumn;
+  }
+
+  var tmp = Error.prototype.constructor.call(this, message);
 
   // Unfortunately errors are not enumerable in Chrome (at least), so `for prop in tmp` doesn't work.
   for (var idx = 0; idx < errorProps.length; idx++) {
     this[errorProps[idx]] = tmp[errorProps[idx]];
   }
+
+  if (line) {
+    this.lineNumber = line;
+    this.column = node.firstColumn;
+  }
 }
 
 Exception.prototype = new Error();

lib/handlebars/runtime.js

@@ -10,11 +10,11 @@ export function checkRevision(compilerInfo) {
     if (compilerRevision < currentRevision) {
       var runtimeVersions = REVISION_CHANGES[currentRevision],
           compilerVersions = REVISION_CHANGES[compilerRevision];
-      throw new Error("Template was precompiled with an older version of Handlebars than the current runtime. "+
+      throw new Exception("Template was precompiled with an older version of Handlebars than the current runtime. "+
             "Please update your precompiler to a newer version ("+runtimeVersions+") or downgrade your runtime to an older version ("+compilerVersions+").");
     } else {
       // Use the embedded version info since the runtime doesn't know about this revision yet
-      throw new Error("Template was precompiled with a newer version of Handlebars than the current runtime. "+
+      throw new Exception("Template was precompiled with a newer version of Handlebars than the current runtime. "+
             "Please update your runtime to a newer version ("+compilerInfo[1]+").");
     }
   }
@@ -24,7 +24,7 @@ export function checkRevision(compilerInfo) {
 
 export function template(templateSpec, env) {
   if (!env) {
-    throw new Error("No environment passed to template");
+    throw new Exception("No environment passed to template");
   }
 
   // Note: Using env.VM references rather than local var references throughout this section to allow

spec/ast.js

@@ -78,8 +78,8 @@ describe('ast', function() {
       shouldThrow(function() {
         var sexprNode = new handlebarsEnv.AST.SexprNode([{ original: 'foo'}], null);
         var mustacheNode = new handlebarsEnv.AST.MustacheNode(sexprNode, null, '{{', {});
-        new handlebarsEnv.AST.BlockNode(mustacheNode, {}, {}, {path: {original: 'bar'}});
-      }, Handlebars.Exception, "foo doesn't match bar");
+        new handlebarsEnv.AST.BlockNode(mustacheNode, {}, {}, {path: {original: 'bar'}}, {first_line: 2, first_column: 2});
+      }, Handlebars.Exception, "foo doesn't match bar - 2:2");
     });
 
     it('stores location info', function(){
@@ -102,22 +102,22 @@ describe('ast', function() {
           {part: 'foo'},
           {part: '..'},
           {part: 'bar'}
-        ]);
-      }, Handlebars.Exception, "Invalid path: foo..");
+        ], {first_line: 1, first_column: 1});
+      }, Handlebars.Exception, "Invalid path: foo.. - 1:1");
       shouldThrow(function() {
         new handlebarsEnv.AST.IdNode([
           {part: 'foo'},
           {part: '.'},
           {part: 'bar'}
-        ]);
-      }, Handlebars.Exception, "Invalid path: foo.");
+        ], {first_line: 1, first_column: 1});
+      }, Handlebars.Exception, "Invalid path: foo. - 1:1");
       shouldThrow(function() {
         new handlebarsEnv.AST.IdNode([
           {part: 'foo'},
           {part: 'this'},
           {part: 'bar'}
-        ]);
-      }, Handlebars.Exception, "Invalid path: foothis");
+        ], {first_line: 1, first_column: 1});
+      }, Handlebars.Exception, "Invalid path: foothis - 1:1");
     });
 
     it('stores location info', function(){
@@ -216,7 +216,7 @@ describe('ast', function() {
           firstColumn: 0,
           lastColumn: 0
         };
-        var pn = new handlebarsEnv.AST.ProgramNode([], {strip: {}}, [ clone ], LOCATION_INFO);
+        pn = new handlebarsEnv.AST.ProgramNode([], {strip: {}}, [ clone ], LOCATION_INFO);
         testLocationInfoStorage(pn);
 
         // Assert that the newly created ProgramNode has the same location