Support style mapping for highlights

NEWS

@@ -1,6 +1,6 @@
 # 1.8.0
 
-* Support parsing of run highlights.
+* Add style mapping for highlights.
 
 # 1.7.1
 

README.md

@@ -460,6 +460,43 @@ small-caps
 Note that this matches text that has had small caps explicitly applied to it.
 It will not match any text that is small caps because of its paragraph or run style.
 
+#### Highlight
+
+Match explicitly highlighted text:
+
+```
+highlight
+```
+
+Note that this matches text that has had a highlight explicitly applied to it.
+It will not match any text that is highlighted because of its paragraph or run style.
+
+It's also possible to match specific colours.
+For instance, to match yellow highlights:
+
+```
+highlight[color='yellow']
+```
+
+The set of colours typically used are:
+
+* `black`
+* `blue`
+* `cyan`
+* `green`
+* `magenta`
+* `red`
+* `yellow`
+* `white`
+* `darkBlue`
+* `darkCyan`
+* `darkGreen`
+* `darkMagenta`
+* `darkRed`
+* `darkYellow`
+* `darkGray`
+* `lightGray`
+
 #### Ignoring document elements
 
 Use `!` to ignore a document element.

src/main/java/org/zwobble/mammoth/internal/conversion/DocumentToHtml.java

@@ -159,6 +159,11 @@ public List<HtmlNode> visit(Paragraph paragraph, Context context) {
         @Override
         public List<HtmlNode> visit(Run run, Context context) {
             Supplier<List<HtmlNode>> nodes = () -> convertChildrenToHtml(run, context);
+            if (run.getHighlight().isPresent()) {
+                nodes = styleMap.getHighlightHtmlPath(run.getHighlight().get())
+                    .orElse(HtmlPath.EMPTY)
+                    .wrap(nodes);
+            }
             if (run.isSmallCaps()) {
                 nodes = styleMap.getSmallCaps().orElse(HtmlPath.EMPTY).wrap(nodes);
             }

src/main/java/org/zwobble/mammoth/internal/styles/StyleMap.java

@@ -131,4 +131,9 @@ public Optional<HtmlPath> getBreakHtmlPath(Break breakElement) {
         return tryFind(breakStyles, styleMapping -> styleMapping.matches(breakElement))
             .map(StyleMapping::getHtmlPath);
     }
+
+    public Optional<HtmlPath> getHighlightHtmlPath(String color) {
+        return tryFind(highlightStyles, styleMapping -> styleMapping.matches(color))
+            .map(StyleMapping::getHtmlPath);
+    }
 }

src/test/java/org/zwobble/mammoth/tests/conversion/DocumentToHtmlTests.java

@@ -210,6 +210,50 @@ public void smallCapsCanBeMappedUsingStyleMapping() {
             deepEquals(list(Html.element("span", list(Html.text("Hello"))))));
     }
 
+    @Test
+    public void highlightedRunsAreIgnoredByDefault() {
+        Run run = run(withHighlight("yellow"), withChildren(new Text("Hello")));
+
+        List<HtmlNode> result = convertToHtml(run);
+
+        assertThat(result, deepEquals(list(Html.text("Hello"))));
+    }
+
+    @Test
+    public void highlightedRunsCanBeConfiguredWithStyleMappingForAllHighlights() {
+        Run run = run(withHighlight("yellow"), withChildren(new Text("Hello")));
+        StyleMap styleMap = StyleMap.builder()
+            .mapHighlight(new HighlightMatcher(Optional.empty()), HtmlPath.element("mark"))
+            .build();
+
+        List<HtmlNode> result = convertToHtml(run, styleMap);
+
+        assertThat(result, deepEquals(list(
+            Html.element("mark", list(Html.text("Hello")))
+        )));
+    }
+
+    @Test
+    public void highlightedRunsCanBeConfiguredWithStyleMappingForSpecificHighlightColor() {
+        Paragraph paragraph = paragraph(withChildren(
+            run(withHighlight("yellow"), withChildren(new Text("Yellow"))),
+            run(withHighlight("red"), withChildren(new Text("Red")))
+        ));
+        StyleMap styleMap = StyleMap.builder()
+            .mapHighlight(new HighlightMatcher(Optional.of("yellow")), HtmlPath.element("mark", map("class", "yellow")))
+            .mapHighlight(new HighlightMatcher(Optional.empty()), HtmlPath.element("mark"))
+            .build();
+
+        List<HtmlNode> result = convertToHtml(paragraph, styleMap);
+
+        assertThat(result, deepEquals(list(
+            Html.element("p", list(
+                Html.element("mark", map("class", "yellow"), list(Html.text("Yellow"))),
+                Html.element("mark", list(Html.text("Red")))
+            ))
+        )));
+    }
+
     @Test
     public void superscriptRunsAreWrappedInSuperscriptTags() {
         assertThat(

src/test/java/org/zwobble/mammoth/tests/documents/DocumentElementMakers.java

@@ -64,6 +64,10 @@ public static Argument<Boolean> withSmallCaps(boolean smallCaps) {
         return arg(SMALL_CAPS, smallCaps);
     }
 
+    public static Argument<Optional<String>> withHighlight(String highlight) {
+        return arg(HIGHLIGHT, Optional.of(highlight));
+    }
+
     public static Argument<VerticalAlignment> withVerticalAlignment(VerticalAlignment verticalAlignment) {
         return arg(VERTICAL_ALIGNMENT, verticalAlignment);
     }