Generate warnings for not-understood style mappings and continue

6 files changed, 54 insertions, 13 deletions

diff --git a/NEWS b/NEWS
index 7fdc2e3..ae800c4 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,9 @@
 
 * When the styleMap option is passed as a string, ignore lines beginning with #.
 
+* Generate warnings for not-understood style mappings and continue, rather than
+  stopping with an error.
+
 # 0.3.24
 
 * Ignore w:numPr elements without w:numId or w:ilvl children.
diff --git a/lib/index.js b/lib/index.js
index a988745..983a32a 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -4,6 +4,7 @@ var DocumentConverter = require("./document-to-html").DocumentConverter;
 var readStyle = require("./style-reader").readStyle;
 var readOptions = require("./options-reader").readOptions;
 var unzip = require("./unzip");
+var Result = require("./results").Result;
 
 exports.convertToHtml = convertToHtml;
 exports.convertToMarkdown = convertToMarkdown;
@@ -50,13 +51,26 @@ function convert(input, options) {
 
 function convertDocumentToHtml(documentResult, options) {
     var parsedOptions = Object.create(options);
-    parsedOptions.styleMap = (options.styleMap || []).map(readStyle);
+    var styleMapResult = parseStyleMap(options.styleMap);
+    parsedOptions.styleMap = styleMapResult.value;
     var documentConverter = new DocumentConverter(parsedOptions);
+    
     return documentResult.flatMapThen(function(document) {
-        return documentConverter.convertToHtml(document);
+        return styleMapResult.flatMapThen(function(styleMap) {
+            return documentConverter.convertToHtml(document);
+        });
     });
 }
 
+function parseStyleMap(styleMap) {
+    return Result.combine((styleMap || []).map(readStyle))
+        .map(function(styleMap) {
+            return styleMap.filter(function(styleMapping) {
+                return !!styleMapping;
+            });
+        });
+}
+
 
 function extractRawText(input) {
     return unzip.openZip(input)
diff --git a/lib/results.js b/lib/results.js
index bd66430..e86d171 100644
--- a/lib/results.js
+++ b/lib/results.js
@@ -2,6 +2,7 @@ var _ = require("underscore");
 
 
 exports.Result = Result;
+exports.success = success;
 exports.warning = warning;
 
 
@@ -32,6 +33,10 @@ Result.combine = function(results) {
     return new Result(values, messages);
 };
 
+function success(value) {
+    return new Result(value, []);
+}
+
 function warning(message) {
     return {
         type: "warning",
diff --git a/lib/style-reader.js b/lib/style-reader.js
index 6a86eab..6d36c42 100644
--- a/lib/style-reader.js
+++ b/lib/style-reader.js
@@ -4,6 +4,7 @@ var RegexTokeniser = lop.RegexTokeniser;
 
 var documentMatchers = require("./document-matchers");
 var htmlPaths = require("./html-paths");
+var results = require("../lib/results");
 
 exports.readHtmlPath = readHtmlPath;
 exports.readDocumentMatcher = readDocumentMatcher;
@@ -195,18 +196,21 @@ function parseString(rule, string) {
     var tokens = tokenise(string);
     var parser = lop.Parser();
     var parseResult = parser.parseTokens(rule, tokens);
-    if (!parseResult.isSuccess()) {
-        throw new Error("Failed to parse: " + describeFailure(parseResult));
+    if (parseResult.isSuccess()) {
+        return results.success(parseResult.value());
+    } else {
+        return new results.Result(null, [results.warning(describeFailure(string, parseResult))]);
     }
-    return parseResult.value();
 }
 
-function describeFailure(parseResult) {
-    return parseResult.errors().map(describeError).join("\n");
+function describeFailure(input, parseResult) {
+    return "Did not understand this style mapping, so ignored it: " + input + "\n" +
+        parseResult.errors().map(describeError).join("\n");
+}
 
-    function describeError(error) {
-        return error.describe();
-    }
+function describeError(error) {
+    return "Error was at character number " + error.characterNumber() + ": " +
+        "Expected " + error.expected + " but got " + error.actual;
 }
 
 function tokenise(string) {
diff --git a/tests/mammoth.tests.js b/tests/mammoth.tests.js
index 6fdd60f..64439f1 100644
--- a/tests/mammoth.tests.js
+++ b/tests/mammoth.tests.js
@@ -4,6 +4,7 @@ var fs = require("fs");
 
 var mammoth = require("../");
 var promises = require("../lib/promises");
+var results = require("../lib/results");
 
 var testing = require("./testing");
 var test = testing.test;
@@ -95,6 +96,19 @@ describe('mammoth', function() {
             });
     });
     
+    test('warning if style mapping is not understood', function() {
+        var docxPath = path.join(__dirname, "test-data/single-paragraph.docx");
+        var options = {
+            styleMap: "!!!!\np => h1"
+        };
+        return mammoth.convertToHtml({path: docxPath}, options).then(function(result) {
+            assert.equal("<h1>Walking on imported air</h1>", result.value);
+            var warning = "Did not understand this style mapping, so ignored it: !!!!\n" +
+                'Error was at character number 1: Expected element type but got unrecognisedCharacter "!"';
+            assert.deepEqual(result.messages, [results.warning(warning)]);
+        });
+    });
+    
     test('options are passed to document converter when calling mammoth.convertToHtml', function() {
         var docxFile = createFakeDocxFile({
             "word/document.xml": testData("simple/word/document.xml")
diff --git a/tests/style-reader.tests.js b/tests/style-reader.tests.js
index 5082a40..76d3f97 100644
--- a/tests/style-reader.tests.js
+++ b/tests/style-reader.tests.js
@@ -2,6 +2,7 @@ var assert = require("assert");
 var htmlPaths = require("../lib/html-paths");
 var documentMatchers = require("../lib/document-matchers");
 var styleReader = require("../lib/style-reader");
+var results = require("../lib/results");
 var test = require("./testing").test;
 
 
@@ -54,7 +55,7 @@ describe('styleReader.readHtmlPath', function() {
     });
     
     function assertHtmlPath(input, expected) {
-        assert.deepEqual(readHtmlPath(input), expected);
+        assert.deepEqual(readHtmlPath(input), results.success(expected));
     }
 });
 
@@ -113,7 +114,7 @@ describe("styleReader.readDocumentMatcher", function() {
     });
     
     function assertDocumentMatcher(input, expected) {
-        assert.deepEqual(readDocumentMatcher(input), expected);
+        assert.deepEqual(readDocumentMatcher(input), results.success(expected));
     }
 });
 
@@ -139,6 +140,6 @@ describe("styleReader.read", function() {
     });
     
     function assertStyleMapping(input, expected) {
-        assert.deepEqual(readStyle(input), expected);
+        assert.deepEqual(readStyle(input), results.success(expected));
     }
 });