Normalize template errors

Author: SamyPesse

lib/book.js

@@ -235,8 +235,15 @@ Book.prototype.generate = function(generator) {
                 return _.reduce(ops["content"] || [], function(prev, file, i) {
                     return prev.then(function() {
                         var p = ((i*100)/nFiles).toFixed(0)+"%";
-                        that.log.info.ln("processing", file, p);
-                        return Q(generator.convertFile(file));
+                        that.log.debug.ln("processing", file, p);
+
+                        return Q(generator.convertFile(file))
+                        .fail(function(err) {
+                            // Transform error message to signal file
+                            throw that.normError(err, {
+                                fileName: file
+                            });
+                        });
                     });
                 }, Q());
             });
@@ -734,6 +741,32 @@ Book.prototype.i18n = function(phrase) {
     return i18n.__.apply({}, [this.config.normalizeLanguage()].concat(args));
 };
 
+// Normalize error
+Book.prototype.normError = function(err, opts) {
+    opts = _.defaults(opts || {}, {
+
+    });
+
+    if (_.isString(err)) err = new Error(err);
+
+    // Extend err
+    _.extend(err, opts);
+
+    err.lineNumber = err.lineNumber || err.lineno;
+    err.columnNumber = err.columnNumber || err.colno;
+
+    err.toString = function() {
+        var attributes = [];
+
+        if (this.fileName) attributes.push("In file '"+this.fileName+"'");
+        if (this.lineNumber) attributes.push("Line "+this.lineNumber);
+        if (this.columnNumber) attributes.push("Column "+this.columnNumber);
+        return (this.name || "Error")+": "+this.message+((attributes.length > 0)? " ("+attributes.join(", ")+")" : "")
+    }
+
+    return err;
+};
+
 // Init and return a book
 Book.init = function(root) {
     var book = new Book(root);

lib/template.js

@@ -331,7 +331,13 @@ TemplateEngine.prototype.renderString = function(content, context, options) {
     // Replace shortcuts
     content = _.reduce(this.shortcuts, _.partial(this._applyShortcut.bind(this), options.type), content);
 
-    return Q.nfcall(this.env.renderString.bind(this.env), content, context, options);
+    return Q.nfcall(this.env.renderString.bind(this.env), content, context, options)
+    .fail(function(err) {
+        if (_.isString(err)) err = new Error(err);
+        err.message = err.message.replace(/^Error: /, "");
+
+        throw err;
+    });
 };
 
 // Render a file from the book