Extract parts of a big switch into helper methods.

This switch is only going to get bigger as we add support for more Markdown constructs that require special handling.

No functional change is intended.

PiperOrigin-RevId: 903448998

Author: eamonnmcmanus

core/src/main/java/com/google/googlejavaformat/java/javadoc/MarkdownPositions.java

@@ -87,42 +87,8 @@ void visit(Node node) {
         case Paragraph paragraph -> addSpan(paragraph, PARAGRAPH_OPEN_TOKEN, PARAGRAPH_CLOSE_TOKEN);
         case BulletList bulletList -> addSpan(bulletList, LIST_OPEN_TOKEN, LIST_CLOSE_TOKEN);
         case OrderedList orderedList -> addSpan(orderedList, LIST_OPEN_TOKEN, LIST_CLOSE_TOKEN);
-        case ListItem listItem -> {
-          int startPosition = listItem.getSourceSpans().getFirst().getInputIndex();
-          Matcher matcher =
-              LIST_ITEM_START_PATTERN.matcher(input).region(startPosition, input.length());
-          verify(matcher.lookingAt());
-          ListItemOpenTag openToken = new ListItemOpenTag(matcher.group(1));
-          addSpan(listItem, openToken, LIST_ITEM_CLOSE_TOKEN);
-          if (listItem.getFirstChild() instanceof Paragraph paragraph) {
-            // A ListItem typically contains a Paragraph, but we don't want to visit that Paragraph
-            // because that would lead us to introduce a line break after the list introduction
-            // (the `-` or whatever). So we visit the children and siblings of the Paragraph
-            // instead.
-            alreadyVisitedChildren = true;
-            visitNodeList(paragraph.getFirstChild());
-            visitNodeList(paragraph.getNext());
-          }
-        }
-        case FencedCodeBlock fencedCodeBlock -> {
-          // Any indentation before the code block is part of FencedCodeBlock. This makes sense
-          // because the lines inside the code block must also be indented by that amount. That
-          // indentation gets subtracted from FencedCodeBlock.getLiteral(), which is the actual text
-          // represented by the code block.
-          int start = startPosition(fencedCodeBlock) + fencedCodeBlock.getFenceIndent();
-          MarkdownFencedCodeBlock token =
-              new MarkdownFencedCodeBlock(
-                  input.substring(start, endPosition(fencedCodeBlock)),
-                  fencedCodeBlock
-                          .getFenceCharacter()
-                          .repeat(fencedCodeBlock.getOpeningFenceLength())
-                      + fencedCodeBlock.getInfo(),
-                  fencedCodeBlock
-                      .getFenceCharacter()
-                      .repeat(fencedCodeBlock.getClosingFenceLength()),
-                  fencedCodeBlock.getLiteral());
-          positionToToken.get(start).addLast(token);
-        }
+        case ListItem listItem -> alreadyVisitedChildren = visitListItem(listItem);
+        case FencedCodeBlock fencedCodeBlock -> visitFencedCodeBlock(fencedCodeBlock);
         // TODO: others
         default -> {}
       }
@@ -131,6 +97,43 @@ void visit(Node node) {
       }
     }
 
+    // Returns true if this method visited the children of the given ListItem.
+    private boolean visitListItem(ListItem listItem) {
+      int startPosition = listItem.getSourceSpans().getFirst().getInputIndex();
+      Matcher matcher =
+          LIST_ITEM_START_PATTERN.matcher(input).region(startPosition, input.length());
+      verify(matcher.lookingAt());
+      ListItemOpenTag openToken = new ListItemOpenTag(matcher.group(1));
+      addSpan(listItem, openToken, LIST_ITEM_CLOSE_TOKEN);
+      return switch (listItem.getFirstChild()) {
+        case Paragraph paragraph -> {
+          // A ListItem typically contains a Paragraph, but we don't want to visit that Paragraph
+          // because that would lead us to introduce a line break after the list introduction
+          // (the `-` or whatever). So we visit the children and siblings of the Paragraph instead.
+          visitNodeList(paragraph.getFirstChild());
+          visitNodeList(paragraph.getNext());
+          yield true;
+        }
+        default -> false;
+      };
+    }
+
+    private void visitFencedCodeBlock(FencedCodeBlock fencedCodeBlock) {
+      // Any indentation before the code block is part of FencedCodeBlock. This makes sense
+      // because the lines inside the code block must also be indented by that amount. That
+      // indentation gets subtracted from FencedCodeBlock.getLiteral(), which is the actual text
+      // represented by the code block.
+      int start = startPosition(fencedCodeBlock) + fencedCodeBlock.getFenceIndent();
+      MarkdownFencedCodeBlock token =
+          new MarkdownFencedCodeBlock(
+              input.substring(start, endPosition(fencedCodeBlock)),
+              fencedCodeBlock.getFenceCharacter().repeat(fencedCodeBlock.getOpeningFenceLength())
+                  + fencedCodeBlock.getInfo(),
+              fencedCodeBlock.getFenceCharacter().repeat(fencedCodeBlock.getClosingFenceLength()),
+              fencedCodeBlock.getLiteral());
+      positionToToken.get(start).addLast(token);
+    }
+
     /**
      * Visits the given node and the other nodes that are reachable from it via the {@link
      * Node#getNext()} references. Does nothing if {@code node} is null.