Preliminary support for dartdoc hovers. Future CLs will give us richer hover information and styl...

editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/utilities/dartdoc/DartDocUtilities.java

Index: editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/utilities/dartdoc/DartDocUtilities.java
===================================================================
--- editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/utilities/dartdoc/DartDocUtilities.java	(revision 0)
+++ editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/utilities/dartdoc/DartDocUtilities.java	(revision 0)
@@ -0,0 +1,112 @@
+package com.google.dart.tools.core.utilities.dartdoc;
+
+import com.google.dart.compiler.ast.DartUnit;
+import com.google.dart.tools.core.model.CompilationUnit;
+import com.google.dart.tools.core.model.DartDocumentable;
+import com.google.dart.tools.core.model.DartElement;
+import com.google.dart.tools.core.model.DartModelException;
+import com.google.dart.tools.core.model.SourceRange;
+import com.google.dart.tools.core.utilities.ast.DartElementLocator;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.StringReader;
+
+/**
+ * A utility class for dealing with Dart doc text.
+ */
+public final class DartDocUtilities {
+
+  /**
+   * Convert from a Dart doc string with slashes and stars to a plain text representation of the
+   * comment.
+   * 
+   * @param str
+   * @return
+   */
+  public static String cleanDartDoc(String str) {
+    // Remove /** */
+    if (str.startsWith("/**")) {
+      str = str.substring(3);
+    }
+
+    if (str.endsWith("*/")) {
+      str = str.substring(0, str.length() - 2);
+    }
+
+    str = str.trim();
+
+    // Remove leading '* ', and turn empty lines into \n's.
+    StringBuilder builder = new StringBuilder();
+
+    BufferedReader reader = new BufferedReader(new StringReader(str));
+
+    try {
+      String line = reader.readLine();
+      int lineCount = 0;
+
+      while (line != null) {
+        line = line.trim();
+
+        if (line.startsWith("*")) {
+          line = line.substring(1).trim();
+        }
+
+        if (line.length() == 0) {
+          lineCount = 0;
+          builder.append("\n\n");
+        } else {
+          if (lineCount > 0) {
+            builder.append(" ");
+          }
+
+          builder.append(line);
+          lineCount++;
+        }
+
+        line = reader.readLine();
+      }
+    } catch (IOException exception) {
+      // this will never be thrown
+    }
+
+    return builder.toString();
+  }
+
+  /**
+   * Return the raw Dart doc string for the element in the given location, if any.
+   * 
+   * @param compilationUnit
+   * @param unit
+   * @param start
+   * @param end
+   * @return
+   * @throws DartModelException
+   */
+  public static String getDartDoc(CompilationUnit compilationUnit, DartUnit unit, int start, int end)
+      throws DartModelException {
+    DartElementLocator locator = new DartElementLocator(compilationUnit, start, end);
+
+    DartElement element = locator.searchWithin(unit);
+
+    if (element instanceof DartDocumentable) {
+      DartDocumentable documentable = (DartDocumentable) element;
+
+      if (documentable.getDartDocRange() != null) {
+        SourceRange range = documentable.getDartDocRange();
+
+        String dartDoc = element.getOpenable().getBuffer().getText(range.getOffset(),
+            range.getLength());
+
+        return cleanDartDoc(dartDoc);
+      }
+    }
+
+    return null;
+  }
+
+  private DartDocUtilities() {
+
+  }
+
+}