Add file, row and column for ui/builder errors

apps/tests/xml-declaration/errors/non-existing-element.xml

@@ -0,0 +1,14 @@
+<Page shownModally="onShownModally">
+  <StackLayout>
+	<!--
+		At first I was going to put "MenuItem",
+		as per https://github.com/NativeScript/NativeScript/issues/501,
+		but then again we may re-introduce "MenuItem" in future and blow this test up.
+		So here is something unique that has better chance not to appear.
+		This comment also offsets error's row and column numbers so if you edit,
+		please do so beyond the unicorn.
+	-->
+    <Unicorn backgroundColor="pink" />
+    <Label text="Modal Page" />
+  </StackLayout>
+</Page>

apps/tests/xml-declaration/xml-declaration-tests.ts

@@ -835,4 +835,24 @@ export function test_parse_template_property() {
     var button = <Button>templateView.getChildAt(0);
     TKUnit.assert(button, "Expected the TemplateView's template to create a button child.");
     TKUnit.assertEqual(button.text, "Click!", "Expected child Button to have text 'Click!'");
-}
+}
+
+export function test_ParserError() {
+    var basePath = "xml-declaration/";
+	var expectedErrorStart =
+		"Building UI from XML. @file:///app/" + basePath + "errors/non-existing-element.xml:11:5\n" +
+ 		" ↳Module 'ui/unicorn' not found for element 'Unicorn'.\n";
+	if (global.android) {
+		expectedErrorStart += "   ↳Module \"ui/unicorn\" not found";
+	} else {
+		expectedErrorStart += "   ↳Failed to find module 'ui/unicorn'";
+	}
+
+	var message;
+	try {
+		builder.load(__dirname + "/errors/non-existing-element.xml");
+	} catch(e) {
+		message = e.message;
+	}
+	TKUnit.assertEqual(message.substr(0, expectedErrorStart.length), expectedErrorStart, "Expected load to throw, and the message to start with specific string");
+}

tsconfig.json

@@ -319,8 +319,8 @@
         "apps/tests/xml-declaration/mainPage.ts",
         "apps/tests/xml-declaration/mymodule/MyControl.ts",
         "apps/tests/xml-declaration/mymodulewithxml/MyControl.ts",
-        "apps/tests/xml-declaration/xml-declaration-tests.ts",
         "apps/tests/xml-declaration/template-builder-tests/template-view.ts",
+        "apps/tests/xml-declaration/xml-declaration-tests.ts",
         "apps/tests/xml-parser-tests/xml-parser-tests.ts",
         "apps/transforms/app.ts",
         "apps/transforms/main-page.ts",
@@ -658,6 +658,8 @@
         "ui/web-view/web-view.android.ts",
         "ui/web-view/web-view.d.ts",
         "ui/web-view/web-view.ios.ts",
+        "utils/debug.d.ts",
+        "utils/debug.ts",
         "utils/module-merge.ts",
         "utils/number-utils.ts",
         "utils/types.d.ts",

ui/builder/builder.ts

@@ -9,6 +9,7 @@ import definition = require("ui/builder");
 import page = require("ui/page");
 import fileResolverModule = require("file-system/file-name-resolver");
 import trace = require("trace");
+import debug = require("utils/debug");
 
 var KNOWNCOLLECTIONS = "knownCollections";
 
@@ -41,7 +42,7 @@ export function parse(value: string | view.Template, context: any): view.View {
     }
 }
 
-function parseInternal(value: string, context: any): componentBuilder.ComponentModule {
+function parseInternal(value: string, context: any, uri?: string): componentBuilder.ComponentModule {
     var currentPage: page.Page;
     var rootComponentModule: componentBuilder.ComponentModule;
     // Temporary collection used for parent scope.
@@ -51,134 +52,148 @@ function parseInternal(value: string, context: any): componentBuilder.ComponentM
     var templateBuilder: templateBuilderDef.TemplateBuilder;
 
     var currentPlatformContext: string;
+    
+    var wrapSource: (e: Error, p: xml.Position) => Error;
+    if (debug.debug && uri) {
+        wrapSource = (e: Error, p: xml.Position) => {
+            var source = new debug.Source(uri, p.line, p.column);
+            e = new debug.SourceError(e, source, "Building UI from XML.");
+            return e;
+        }
+    } else {
+        wrapSource = e => e; // no-op identity
+    }    
 
     // Parse the XML.
     var xmlParser = new xml.XmlParser((args: xml.ParserEvent) => {
-
-        if (args.eventType === xml.ParserEventType.StartElement) {
-            if (isPlatform(args.elementName)) {
-
-                if (currentPlatformContext) {
-                    throw new Error("Already in '" + currentPlatformContext + "' platform context and cannot switch to '" + args.elementName + "' platform! Platform tags cannot be nested.");
+        try {
+            if (args.eventType === xml.ParserEventType.StartElement) {
+                if (isPlatform(args.elementName)) {
+    
+                    if (currentPlatformContext) {
+                        throw new Error("Already in '" + currentPlatformContext + "' platform context and cannot switch to '" + args.elementName + "' platform! Platform tags cannot be nested.");
+                    }
+    
+                    currentPlatformContext = args.elementName;
+                    return;
                 }
-
-                currentPlatformContext = args.elementName;
+            }
+    
+            if (args.eventType === xml.ParserEventType.EndElement) {
+                if (isPlatform(args.elementName)) {
+                    currentPlatformContext = undefined;
+                    return;
+                }
+            }
+    
+            if (currentPlatformContext && !isCurentPlatform(currentPlatformContext)) {
                 return;
             }
-        }
-
-        if (args.eventType === xml.ParserEventType.EndElement) {
-            if (isPlatform(args.elementName)) {
-                currentPlatformContext = undefined;
-                return;
+    
+            if (templateBuilder) {
+                var finished = templateBuilder.handleElement(args);
+                if (finished) {
+                    // Clean-up and continnue
+                    templateBuilder = undefined;
+                }
+                else {
+                    // Skip processing untill the template builder finishes his job.
+                    return;
+                }
             }
-        }
-
-        if (currentPlatformContext && !isCurentPlatform(currentPlatformContext)) {
-            return;
-        }
-
-        if (templateBuilder) {
-            var finished = templateBuilder.handleElement(args);
-            if (finished) {
-                // Clean-up and continnue
-                templateBuilder = undefined;
-            }
-            else {
-                // Skip processing untill the template builder finishes his job.
-                return;
-            }
-        }
-
-        // Get the current parent.
-        var parent = parents[parents.length - 1];
-        var complexProperty = complexProperties[complexProperties.length - 1];
-
-        // Create component instance from every element declaration.
-        if (args.eventType === xml.ParserEventType.StartElement) {
-            if (isComplexProperty(args.elementName)) {
-
-                var name = getComplexProperty(args.elementName);
-
-                complexProperties.push({
-                    parent: parent,
-                    name: name,
-                    items: [],
-                });
-
-                if (templateBuilderDef.isKnownTemplate(name, parent.exports)) {
-                    templateBuilder = new templateBuilderDef.TemplateBuilder({
-                        context: parent ? getExports(parent.component) : null, // Passing 'context' won't work if you set "codeFile" on the page
+    
+            // Get the current parent.
+            var parent = parents[parents.length - 1];
+            var complexProperty = complexProperties[complexProperties.length - 1];
+    
+            // Create component instance from every element declaration.
+            if (args.eventType === xml.ParserEventType.StartElement) {
+                if (isComplexProperty(args.elementName)) {
+    
+                    var name = getComplexProperty(args.elementName);
+    
+                    complexProperties.push({
                         parent: parent,
                         name: name,
-                        elementName: args.elementName,
-                        templateItems: []
+                        items: [],
                     });
-                }
-
-            } else {
-
-                var componentModule: componentBuilder.ComponentModule;
-
-                if (args.prefix && args.namespace) {
-                    // Custom components
-                    componentModule = loadCustomComponent(args.namespace, args.elementName, args.attributes, context, currentPage);
+    
+                    if (templateBuilderDef.isKnownTemplate(name, parent.exports)) {
+                        templateBuilder = new templateBuilderDef.TemplateBuilder({
+                            context: parent ? getExports(parent.component) : null, // Passing 'context' won't work if you set "codeFile" on the page
+                            parent: parent,
+                            name: name,
+                            elementName: args.elementName,
+                            templateItems: []
+                        });
+                    }
+    
                 } else {
-                    // Default components
-                    componentModule = componentBuilder.getComponentModule(args.elementName, args.namespace, args.attributes, context);
-                }
-
-                if (componentModule) {
-                    if (parent) {
-                        if (componentModule.component instanceof view.View) {
-                            if (complexProperty) {
-                                // Add to complex property to component.
-                                addToComplexProperty(parent, complexProperty, componentModule)
+    
+                    var componentModule: componentBuilder.ComponentModule;
+    
+                    if (args.prefix && args.namespace) {
+                        // Custom components
+                        componentModule = loadCustomComponent(args.namespace, args.elementName, args.attributes, context, currentPage);
+                    } else {
+                        // Default components
+                        componentModule = componentBuilder.getComponentModule(args.elementName, args.namespace, args.attributes, context);
+                    }
+    
+                    if (componentModule) {
+                        if (parent) {
+                            if (componentModule.component instanceof view.View) {
+                                if (complexProperty) {
+                                    // Add to complex property to component.
+                                    addToComplexProperty(parent, complexProperty, componentModule)
+                                } else if ((<any>parent.component)._addChildFromBuilder) {
+                                    // Add component to visual tree
+                                    (<any>parent.component)._addChildFromBuilder(args.elementName, componentModule.component);
+                                }
+                            } else if (complexProperty) {
+                                // Add component to complex property of parent component.
+                                addToComplexProperty(parent, complexProperty, componentModule);
                             } else if ((<any>parent.component)._addChildFromBuilder) {
-                                // Add component to visual tree
                                 (<any>parent.component)._addChildFromBuilder(args.elementName, componentModule.component);
                             }
-                        } else if (complexProperty) {
-                            // Add component to complex property of parent component.
-                            addToComplexProperty(parent, complexProperty, componentModule);
-                        } else if ((<any>parent.component)._addChildFromBuilder) {
-                            (<any>parent.component)._addChildFromBuilder(args.elementName, componentModule.component);
+                        } else if (parents.length === 0) {
+                            // Set root component.
+                            rootComponentModule = componentModule;
+    
+                            if (rootComponentModule && rootComponentModule.component instanceof page.Page) {
+                                currentPage = <page.Page>rootComponentModule.component;
+                            }
                         }
-                    } else if (parents.length === 0) {
-                        // Set root component.
-                        rootComponentModule = componentModule;
-
-                        if (rootComponentModule && rootComponentModule.component instanceof page.Page) {
-                            currentPage = <page.Page>rootComponentModule.component;
-                        }
-                    }
-
-                    // Add the component instance to the parents scope collection.
-                    parents.push(componentModule);
-                }
-            }
-
-        } else if (args.eventType === xml.ParserEventType.EndElement) {
-            if (isComplexProperty(args.elementName)) {
-                if (complexProperty) {
-                    if (parent && (<any>parent.component)._addArrayFromBuilder) {
-                        // If parent is AddArrayFromBuilder call the interface method to populate the array property.
-                        (<any>parent.component)._addArrayFromBuilder(complexProperty.name, complexProperty.items);
-                        complexProperty.items = [];
+    
+                        // Add the component instance to the parents scope collection.
+                        parents.push(componentModule);
                     }
                 }
-                // Remove the last complexProperty from the complexProperties collection (move to the previous complexProperty scope).
-                complexProperties.pop();
-
-            } else {
-                // Remove the last parent from the parents collection (move to the previous parent scope).
-                parents.pop();
+    
+            } else if (args.eventType === xml.ParserEventType.EndElement) {
+                if (isComplexProperty(args.elementName)) {
+                    if (complexProperty) {
+                        if (parent && (<any>parent.component)._addArrayFromBuilder) {
+                            // If parent is AddArrayFromBuilder call the interface method to populate the array property.
+                            (<any>parent.component)._addArrayFromBuilder(complexProperty.name, complexProperty.items);
+                            complexProperty.items = [];
+                        }
+                    }
+                    // Remove the last complexProperty from the complexProperties collection (move to the previous complexProperty scope).
+                    complexProperties.pop();
+    
+                } else {
+                    // Remove the last parent from the parents collection (move to the previous parent scope).
+                    parents.pop();
+                }
             }
+    
+        } catch(e) {
+            throw wrapSource(e, args.position);
         }
-
-    }, (e) => {
-            throw new Error("XML parse error: " + e.message);
-        }, true);
+    }, (e, p) => {
+        throw wrapSource(new Error("XML parse error: " + e.message), p);
+    }, true);
 
     if (types.isString(value)) {
         value = value.replace(/xmlns=("|')http:\/\/((www)|(schemas))\.nativescript\.org\/tns\.xsd\1/, "");
@@ -271,7 +286,7 @@ function loadInternal(fileName: string, context?: any): componentBuilder.Compone
             throw new Error("Error loading file " + fileName + " :" + error.message);
         }
         var text = file.readTextSync(onError);
-        componentModule = parseInternal(text, context);
+        componentModule = parseInternal(text, context, fileName);
     }
 
     if (componentModule && componentModule.component) {

ui/builder/component-builder.ts

@@ -5,6 +5,7 @@ import fs = require("file-system");
 import bindingBuilder = require("./binding-builder");
 import platform = require("platform");
 import pages = require("ui/page");
+import debug = require("utils/debug");
 
 //the imports below are needed for special property registration
 import "ui/layouts/dock-layout";
@@ -60,7 +61,7 @@ export function getComponentModule(elementName: string, namespace: string, attri
         // Create instance of the component.
         instance = new instanceType();
     } catch (ex) {
-        throw new Error("Cannot create module " + moduleId + ". " + ex + ". StackTrace: " + ex.stack);
+        throw new debug.ScopeError(ex, "Module '" + moduleId + "' not found for element '" + (namespace ? namespace + ":" : "") + elementName + "'.");
     }
 
     if (attributes) {

utils/debug.d.ts

@@ -0,0 +1,92 @@
+declare module "utils/debug" {
+	/**
+	 * A runtime option indicating whether the build has debugging enabled.
+	 */
+	export var debug: boolean;
+	
+	/**
+	 * A class encapsulating information for source code origin.
+	 */
+	export class Source {
+		
+		/**
+		 * Creates a new Source instance by given uri, line and column.
+		 */
+		constructor(uri: string, line: number, column: number);
+		
+		/**
+		 * Gets the URI of the source document;
+		 */
+		uri: string;
+		
+		/**
+		 * Gets the line in the source document.
+		 */
+		line: number;
+		
+		/**
+		 * Gets the position in the source document.
+		 */
+		column: number;
+	
+		/**
+		 * Get the source of an object.
+		 */
+		public static get(object: any): Source;
+		
+		/**
+		 * Set the source of an object.
+		 */
+		public static set(object: any, src: Source);
+	}
+	
+	/**
+	 * An Error class that provides additional context to an error.
+	 */
+	export class ScopeError implements Error {
+		/**
+		 * Creates a new ScopeError providing addtional context to the child error.
+		 * @param child The child error to extend.
+		 * @param message Additional message to prepend to the child error.
+		 */
+		constructor(child: Error, message?: string);
+		
+		/**
+		 * Gets the child error.
+		 */
+		child: Error;
+		
+		/**
+		 * Gets the error message.
+		 */
+		message: string;
+		
+		/**
+		 * Gets the stack trace.
+		 */
+		stack: string;
+		
+		/**
+		 * Gets the error name.
+		 */
+		name: string;
+	}
+	
+	/**
+	 * Represents a scope error providing addiot
+	 */
+	export class SourceError extends ScopeError {
+		/**
+		 * Creates a new SourceError by child error, source and optional message.
+		 * @param child The child error to extend.
+		 * @param source The source where the error occured.
+		 * @param message Additonal message to prepend along the source location and the child error's message.
+		 */
+		constructor(child: Error, source: Source, message?: string);
+		
+		/**
+		 * Gets the error source.
+		 */
+		source: Source;
+	}
+}

utils/debug.ts

@@ -0,0 +1,83 @@
+import { knownFolders } from "file-system"
+
+export var debug = true;
+
+// TODO: Get this from the runtimes...
+var applicationRootPath = knownFolders.currentApp().path;
+applicationRootPath = applicationRootPath.substr(0, applicationRootPath.length - "app/".length);
+
+export class Source {
+	private _uri: string;
+	private _line: number;
+	private _column: number;
+	
+	private static _source: symbol = Symbol("source");
+	private static _appRoot: string;
+	
+	constructor(uri: string, line: number, column: number) {
+		if (uri.length > applicationRootPath.length && uri.substr(0, applicationRootPath.length) === applicationRootPath) {
+			this._uri = "file://" + uri.substr(applicationRootPath.length);
+		} else {
+			this._uri = uri;
+		}
+		this._line = line;
+		this._column = column;
+	}
+	
+	get uri(): string { return this._uri; }
+	get line(): number { return this._line; }
+	get column(): number { return this._column; }
+	
+	public toString() {
+		return this._uri + ":" + this._line + ":" + this._column;
+	}
+
+	public static get(object: any): Source {
+		return object[Source._source];
+	}
+	
+	public static set(object: any, src: Source) {
+		object[Source._source] = src;
+	}
+}
+
+export class ScopeError implements Error {
+	private _child: Error;
+	private _message: string;
+	
+	constructor(child: Error, message?: string) {
+		if (!child) {
+			throw new Error("Required child error!");
+		}
+		this._child = child;
+		this._message = message;
+	}
+	
+	get child() { return this._child; }
+	get message() {
+		if (this._message && this._childMessage) {
+			// It is a ↳ but the ios fails to show this symbol at the moment.
+			return this._message + "\n \u21B3" + this._childMessage.replace("\n", "\n  ");	
+		}
+		return this._message || this._childMessage || undefined;
+	}
+	get name() { return this.child.name; }
+	get stack() { return (<any>this.child).stack; }
+	
+	private get _childMessage(): string {
+		return this.child.message;
+	}
+	
+	public toString() { return "Error: " + this.message; }
+}
+
+export class SourceError extends ScopeError {
+	private _source: Source;
+	
+	constructor(child: Error, source: Source, message?: string) {
+		super(child, message ? message + " @" + source + "" : source + "");
+		this._source = source;
+	}
+	
+	get source() { return this._source; }
+}

xml/xml.d.ts

@@ -100,18 +100,18 @@ declare module "xml" {
      */
     class XmlParser {
 
-       /**
-        * Creates a new instance of the XmlParser class.
-        * @param onEvent The callback to execute when a parser event occurs. The 'event' parameter contains information about the event.
-        * @param onError The callback to execute when a parser error occurs. The 'error' parameter contains the error.
-        * @param processNamespaces Specifies whether namespaces should be processed.
-        */
-        constructor(onEvent: (event: ParserEvent) => void, onError?: (error: Error) => void, processNamespaces?: boolean, angularSyntax?: boolean);
+        /**
+         * Creates a new instance of the XmlParser class.
+         * @param onEvent The callback to execute when a parser event occurs. The 'event' parameter contains information about the event.
+         * @param onError The callback to execute when a parser error occurs. The 'error' parameter contains the error.
+         * @param processNamespaces Specifies whether namespaces should be processed.
+         */
+        constructor(onEvent: (event: ParserEvent) => void, onError?: (error: Error, position: Position) => void, processNamespaces?: boolean, angularSyntax?: boolean);
         
-       /**
-        * Parses the supplied xml string.
-        * @param xmlString The string containing the xml to parse.
-        */
+        /**
+         * Parses the supplied xml string.
+         * @param xmlString The string containing the xml to parse.
+         */
         parse(xmlString: string): void;
     }
 }