From 2d56c8ad24fab3e77195b1f4db2835140db1518c Mon Sep 17 00:00:00 2001
From: peter <peter@jetbrains.com>
Date: Mon, 30 May 2016 15:57:11 +0200
Subject: [PATCH] IDEA-156772 Some Live Templates lost their "applicable
 context" IntelliJ 2016.2 EAP

---
 .../template/LiveTemplateTest.groovy          | 17 ++++++++--
 .../template/impl/TemplateContext.java        | 31 ++++++++++++++-----
 2 files changed, 39 insertions(+), 9 deletions(-)

diff --git a/java/java-tests/testSrc/com/intellij/codeInsight/template/LiveTemplateTest.groovy b/java/java-tests/testSrc/com/intellij/codeInsight/template/LiveTemplateTest.groovy
index 5cf4f3996813..b4219ced7135 100644
--- a/java/java-tests/testSrc/com/intellij/codeInsight/template/LiveTemplateTest.groovy
+++ b/java/java-tests/testSrc/com/intellij/codeInsight/template/LiveTemplateTest.groovy
@@ -583,6 +583,19 @@ class Outer {
     assert write.children.size() == 3 : JDOMUtil.writeElement(write)
   }
 
+  public void "test use default context when empty"() {
+    def context = new TemplateContext()
+    context.readTemplateContext(new Element("context"))
+
+    def defContext = new TemplateContext()
+    def commentContext = TemplateContextType.EP_NAME.findExtension(JavaCommentContextType)
+    defContext.putValue(commentContext, true)
+
+    context.setDefaultContext(defContext)
+    assert context.isEnabled(commentContext)
+    assert !context.isEnabled(TemplateContextType.EP_NAME.findExtension(JavaCodeContextType.Generic))
+  }
+
   private boolean isApplicable(String text, TemplateImpl inst) throws IOException {
     configureFromFileText("a.java", text);
     return TemplateManagerImpl.isApplicable(myFixture.getFile(), getEditor().getCaretModel().getOffset(), inst);
@@ -1057,7 +1070,7 @@ class Foo {{
 }}
 """
   }
-  
+
   public void "test add new line on enter outside editing variable"() {
     myFixture.configureByText 'a.java', """
 class Foo {{
@@ -1074,7 +1087,7 @@ class Foo {{
 }}
 """
   }
-  
+
   public void "test type tab character on tab outside editing variable"() {
     myFixture.configureByText 'a.java', """
 class Foo {{
diff --git a/platform/lang-impl/src/com/intellij/codeInsight/template/impl/TemplateContext.java b/platform/lang-impl/src/com/intellij/codeInsight/template/impl/TemplateContext.java
index eef4bb1f79ac..1e273434fef4 100644
--- a/platform/lang-impl/src/com/intellij/codeInsight/template/impl/TemplateContext.java
+++ b/platform/lang-impl/src/com/intellij/codeInsight/template/impl/TemplateContext.java
@@ -82,7 +82,8 @@ public class TemplateContext {
   }
 
   // used during initialization => no sync
-  void setDefaultContext(@NotNull TemplateContext defContext) {
+  @VisibleForTesting
+  public void setDefaultContext(@NotNull TemplateContext defContext) {
     HashMap<String, Boolean> copy = new HashMap<String, Boolean>(myContextStates);
     myContextStates.clear();
     myContextStates.putAll(defContext.myContextStates);
@@ -100,14 +101,30 @@ public class TemplateContext {
       }
     }
 
+    myContextStates.putAll(makeInheritanceExplicit());
+  }
+
+  /**
+   * Mark contexts explicitly as excluded which are excluded because some of their bases is explicitly marked as excluded.
+   * Otherwise that `excluded` status will be forgotten if the base context is enabled.
+   */
+  @NotNull
+  private Map<String, Boolean> makeInheritanceExplicit() {
     Map<String, Boolean> explicitStates = ContainerUtil.newHashMap();
-    for (TemplateContextType type : TemplateManagerImpl.getAllContextTypes()) {
-      if (getOwnValue(type) == null) {
-        Iterable<TemplateContextType> bases = JBIterable.generate(type, TemplateContextType::getBaseContextType);
-        explicitStates.put(type.getContextId(), ContainerUtil.getFirstItem(ContainerUtil.mapNotNull(bases, this::getOwnValue), false));
-      }
+    for (TemplateContextType type : ContainerUtil.filter(TemplateManagerImpl.getAllContextTypes(), this::isDisabledByInheritance)) {
+      explicitStates.put(type.getContextId(), false);
     }
-    myContextStates.putAll(explicitStates);
+    return explicitStates;
+  }
+
+  private boolean isDisabledByInheritance(TemplateContextType type) {
+    return !hasOwnValue(type) &&
+           !isEnabled(type) &&
+           JBIterable.generate(type, TemplateContextType::getBaseContextType).filter(this::hasOwnValue).first() != null;
+  }
+
+  private boolean hasOwnValue(TemplateContextType t) {
+    return getOwnValue(t) != null;
   }
 
   @VisibleForTesting