Merge pull request #48 from atlassian/issue-31-attribute-provider-images

Make AttributeProvider work for Image nodes (#31)

Author: robinst

commonmark/src/main/java/org/commonmark/html/HtmlRenderer.java

@@ -304,20 +304,20 @@ public void visit(OrderedList orderedList) {
 
         @Override
         public void visit(Image image) {
-            if (html.isTagAllowed()) {
-                String url = optionallyPercentEncodeUrl(image.getDestination());
-                html.raw("<img src=\"" + escape(url, true) +
-                        "\" alt=\"");
-            }
-            html.disableTags();
-            visitChildren(image);
-            html.enableTags();
-            if (html.isTagAllowed()) {
-                if (image.getTitle() != null) {
-                    html.raw("\" title=\"" + escape(image.getTitle(), true));
-                }
-                html.raw("\" />");
+            String url = optionallyPercentEncodeUrl(image.getDestination());
+
+            AltTextVisitor altTextVisitor = new AltTextVisitor();
+            image.accept(altTextVisitor);
+            String altText = altTextVisitor.getAltText();
+
+            Map<String, String> attrs = new LinkedHashMap<>();
+            attrs.put("src", url);
+            attrs.put("alt", altText);
+            if (image.getTitle() != null) {
+                attrs.put("title", image.getTitle());
             }
+
+            html.tag("img", getAttrs(image, attrs), true);
         }
 
         @Override
@@ -434,4 +434,28 @@ private void setCustomAttributes(Node node, Map<String, String> attrs) {
             }
         }
     }
+
+    private static class AltTextVisitor extends AbstractVisitor {
+
+        private final StringBuilder sb = new StringBuilder();
+
+        String getAltText() {
+            return sb.toString();
+        }
+
+        @Override
+        public void visit(Text text) {
+            sb.append(text.getLiteral());
+        }
+
+        @Override
+        public void visit(SoftLineBreak softLineBreak) {
+            sb.append('\n');
+        }
+
+        @Override
+        public void visit(HardLineBreak hardLineBreak) {
+            sb.append('\n');
+        }
+    }
 }

commonmark/src/main/java/org/commonmark/html/HtmlWriter.java

@@ -5,39 +5,20 @@
 import java.io.IOException;
 import java.util.Collections;
 import java.util.Map;
-import java.util.regex.Pattern;
 
 public class HtmlWriter {
 
     private static final Map<String, String> NO_ATTRIBUTES = Collections.emptyMap();
-    private static final Pattern HTML_TAG_PATTERN = Pattern.compile("<[^>]*>");
 
     private final Appendable buffer;
-    private int nesting = 0;
     private char lastChar = 0;
 
     public HtmlWriter(Appendable out) {
         this.buffer = out;
     }
 
     public void raw(String s) {
-        if (isTagAllowed()) {
-            append(s);
-        } else {
-            append(HTML_TAG_PATTERN.matcher(s).replaceAll(""));
-        }
-    }
-
-    public boolean isTagAllowed() {
-        return nesting == 0;
-    }
-
-    public void disableTags() {
-        nesting++;
-    }
-
-    public void enableTags() {
-        nesting--;
+        append(s);
     }
 
     public void tag(String name) {
@@ -50,10 +31,6 @@ public void tag(String name, Map<String, String> attrs) {
 
     // Helper function to produce an HTML tag.
     public void tag(String name, Map<String, String> attrs, boolean voidElement) {
-        if (!isTagAllowed()) {
-            return;
-        }
-
         append("<");
         append(name);
         if (attrs != null && !attrs.isEmpty()) {

commonmark/src/test/java/org/commonmark/test/HtmlRendererTest.java

@@ -3,6 +3,7 @@
 import org.commonmark.html.AttributeProvider;
 import org.commonmark.html.HtmlRenderer;
 import org.commonmark.node.FencedCodeBlock;
+import org.commonmark.node.Image;
 import org.commonmark.node.Node;
 import org.commonmark.parser.Parser;
 import org.junit.Test;
@@ -77,7 +78,7 @@ public void percentEncodeUrl() {
     }
 
     @Test
-    public void attributeProvider() {
+    public void attributeProviderForCodeBlock() {
         AttributeProvider custom = new AttributeProvider() {
             @Override
             public void setAttributes(Node node, Map<String, String> attributes) {
@@ -99,11 +100,46 @@ public void setAttributes(Node node, Map<String, String> attributes) {
         assertEquals("<pre><code data-custom=\"evil&quot;\">content\n</code></pre>\n", rendered2);
     }
 
+    @Test
+    public void attributeProviderForImage() {
+        AttributeProvider custom = new AttributeProvider() {
+            @Override
+            public void setAttributes(Node node, Map<String, String> attributes) {
+                if (node instanceof Image) {
+                    attributes.remove("alt");
+                    attributes.put("test", "hey");
+                }
+            }
+        };
+
+        HtmlRenderer renderer = HtmlRenderer.builder().attributeProvider(custom).build();
+        String rendered = renderer.render(parse("![foo](/url)\n"));
+        assertEquals("<p><img src=\"/url\" test=\"hey\" /></p>\n", rendered);
+    }
+
     @Test
     public void orderedListStartZero() {
         assertEquals("<ol start=\"0\">\n<li>Test</li>\n</ol>\n", defaultRenderer().render(parse("0. Test\n")));
     }
 
+    @Test
+    public void imageAltTextWithSoftLineBreak() {
+        assertEquals("<p><img src=\"/url\" alt=\"foo\nbar\" /></p>\n",
+                defaultRenderer().render(parse("![foo\nbar](/url)\n")));
+    }
+
+    @Test
+    public void imageAltTextWithHardLineBreak() {
+        assertEquals("<p><img src=\"/url\" alt=\"foo\nbar\" /></p>\n",
+                defaultRenderer().render(parse("![foo  \nbar](/url)\n")));
+    }
+
+    @Test
+    public void imageAltTextWithEntities() {
+        assertEquals("<p><img src=\"/url\" alt=\"foo \u00E4\" /></p>\n",
+                defaultRenderer().render(parse("![foo &auml;](/url)\n")));
+    }
+
     private static HtmlRenderer defaultRenderer() {
         return HtmlRenderer.builder().build();
     }