IDEA-CR-3132 honor exact selection; some javadoc with HTML warnings

platform/lang-api/src/com/intellij/lang/ExpressionTypeProvider.java

@@ -21,15 +21,27 @@ import org.jetbrains.annotations.NotNull;
 import java.util.List;
 
 /**
+ * @see com.intellij.codeInsight.hint.actions.ShowExpressionTypeAction
+ *
  * @author gregsh
  */
 public abstract class ExpressionTypeProvider<T extends PsiElement> {
+  /**
+   * Returns HTML string for type info hint.
+   * @see com.intellij.openapi.util.text.StringUtil#escapeXml(String)
+   */
   @NotNull
   public abstract String getInformationHint(@NotNull T element);
 
+  /**
+   * Returns HTML string if no target found at position.
+   */
   @NotNull
   public abstract String getErrorHint();
 
+  /**
+   * Returns the list of all possible targets at specified position.
+   */
   @NotNull
   public abstract List<T> getExpressionsAt(@NotNull PsiElement elementAt);
 }

platform/lang-impl/src/com/intellij/codeInsight/hint/ShowExpressionTypeHandler.java

@@ -60,11 +60,14 @@ public class ShowExpressionTypeHandler implements CodeInsightActionHandler {
     final Set<ExpressionTypeProvider> handlers = getHandlers(project, language, file.getViewProvider().getBaseLanguage());
     if (handlers.isEmpty()) return;
 
+    boolean exactRange = false;
     TextRange range = EditorUtil.getSelectionInAnyMode(editor);
     final Map<PsiElement, ExpressionTypeProvider> map = ContainerUtil.newLinkedHashMap();
     for (ExpressionTypeProvider handler : handlers) {
       for (PsiElement element : ((ExpressionTypeProvider<? extends PsiElement>)handler).getExpressionsAt(elementAt)) {
-        if (!element.getTextRange().contains(range)) continue;
+        TextRange r = element.getTextRange();
+        if (exactRange && !r.equals(range) || !r.contains(range)) continue;
+        if (!exactRange) exactRange = r.equals(range);
         map.put(element, handler);
       }
     }