Get rid of the getVars method and switch callers to getVarIterable. U…

…sing an Iterable instead of an Iterator generally leads to shorter and less awkward code.

This also lets us get rid of an @Suppress annotation \o/
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=123805778

src/com/google/javascript/jscomp/CoalesceVariableNames.java

@@ -35,7 +35,6 @@
 
 import java.util.Comparator;
 import java.util.Deque;
-import java.util.Iterator;
 import java.util.LinkedList;
 import java.util.Set;
 import java.util.TreeSet;
@@ -174,9 +173,7 @@ public void visit(NodeTraversal t, Node n, Node parent) {
       // make this fast.
       String pseudoName = null;
       Set<String> allMergedNames = new TreeSet<>();
-      for (Iterator<Var> i = t.getScope().getVars(); i.hasNext();) {
-        Var iVar = i.next();
-
+      for (Var iVar : t.getScope().getVarIterable()) {
         // Look for all the variables that can be merged (in the graph by now)
         // and it is merged with the current coalescedVar.
         if (colorings.peek().getGraph().getNode(iVar) != null
@@ -212,8 +209,7 @@ private UndiGraph<Var, Void> computeVariableNamesInterferenceGraph(
     Scope scope = t.getScope();
 
     // First create a node for each non-escaped variable.
-    for (Iterator<Var> i = scope.getVars(); i.hasNext();) {
-      Var v = i.next();
+    for (Var v : scope.getVarIterable()) {
       if (!escaped.contains(v)) {
 
         // TODO(user): In theory, we CAN coalesce function names just like
@@ -229,13 +225,10 @@ private UndiGraph<Var, Void> computeVariableNamesInterferenceGraph(
     }
 
     // Go through each variable and try to connect them.
-    for (Iterator<Var> i1 = scope.getVars(); i1.hasNext();) {
-      Var v1 = i1.next();
+    for (Var v1 : scope.getVarIterable()) {
 
       NEXT_VAR_PAIR:
-      for (Iterator<Var> i2 = scope.getVars(); i2.hasNext();) {
-        Var v2 = i2.next();
-
+      for (Var v2 : scope.getVarIterable()) {
         // Skip duplicate pairs.
         if (v1.index >= v2.index) {
           continue;

src/com/google/javascript/jscomp/DataFlowAnalysis.java

@@ -28,7 +28,6 @@
 
 import java.util.ArrayList;
 import java.util.Comparator;
-import java.util.Iterator;
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Objects;
@@ -577,8 +576,7 @@ public void visit(NodeTraversal t, Node n, Node parent) {
 
     // 1: Remove the exception name in CATCH which technically isn't local to
     //    begin with.
-    for (Iterator<Var> i = jsScope.getVars(); i.hasNext();) {
-      Var var = i.next();
+    for (Var var : jsScope.getVarIterable()) {
       if (var.getParentNode().isCatch() ||
           compiler.getCodingConvention().isExported(var.getName())) {
         escaped.add(var);

src/com/google/javascript/jscomp/Es6RenameVariablesInParamLists.java

@@ -21,7 +21,6 @@
 
 import java.util.HashMap;
 import java.util.HashSet;
-import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.Set;
@@ -71,8 +70,7 @@ public final boolean shouldTraverse(NodeTraversal t, Node n, Node parent) {
     Scope fScope = creator.createScope(n, t.getScope());
     Scope fBlockScope = creator.createScope(block, fScope);
     Map<String, String> currFuncRenameMap = new HashMap<>();
-    for (Iterator<Var> it = fBlockScope.getVars(); it.hasNext();) {
-      Var var = it.next();
+    for (Var var : fBlockScope.getVarIterable()) {
       String oldName = var.getName();
       if (collector.currFuncReferences.contains(oldName)
           && !currFuncRenameMap.containsKey(oldName)) {

src/com/google/javascript/jscomp/InlineObjectLiterals.java

@@ -30,7 +30,6 @@
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
-import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
 import java.util.List;
@@ -83,9 +82,7 @@ private class InliningBehavior implements Behavior {
 
     @Override
     public void afterExitScope(NodeTraversal t, ReferenceMap referenceMap) {
-      for (Iterator<Var> it = t.getScope().getVars(); it.hasNext();) {
-        Var v = it.next();
-
+      for (Var v : t.getScope().getVarIterable()) {
         if (isVarInlineForbidden(v)) {
           continue;
         }

src/com/google/javascript/jscomp/InlineVariables.java

@@ -166,8 +166,7 @@ public void afterExitScope(NodeTraversal t, ReferenceMap referenceMap) {
     private void collectAliasCandidates(NodeTraversal t,
         ReferenceMap referenceMap) {
       if (mode != Mode.CONSTANTS_ONLY) {
-        for (Iterator<Var> it = t.getScope().getVars(); it.hasNext();) {
-          Var v = it.next();
+        for (Var v : t.getScope().getVarIterable()) {
           ReferenceCollection referenceInfo = referenceMap.getReferences(v);
 
           // NOTE(nicksantos): Don't handle variables that are never used.
@@ -195,9 +194,7 @@ private void doInlinesForScope(NodeTraversal t, ReferenceMap referenceMap) {
 
       boolean maybeModifiedArguments =
           maybeEscapedOrModifiedArguments(t.getScope(), referenceMap);
-      for (Iterator<Var> it = t.getScope().getVars(); it.hasNext();) {
-        Var v = it.next();
-
+      for (Var v : t.getScope().getVarIterable()) {
         ReferenceCollection referenceInfo = referenceMap.getReferences(v);
 
         // referenceInfo will be null if we're in constants-only mode

src/com/google/javascript/jscomp/LinkedFlowScope.java

@@ -26,7 +26,6 @@
 import com.google.javascript.rhino.jstype.StaticTypedScope;
 import com.google.javascript.rhino.jstype.StaticTypedSlot;
 
-import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
 import java.util.Map;
@@ -219,8 +218,7 @@ public StaticTypedSlot<JSType> findUniqueRefinedSlot(FlowScope blindScope) {
   @Override
   public void completeScope(StaticTypedScope<JSType> staticScope) {
     TypedScope scope = (TypedScope) staticScope;
-    for (Iterator<TypedVar> it = scope.getVars(); it.hasNext();) {
-      TypedVar var = it.next();
+    for (TypedVar var : scope.getVarIterable()) {
       if (var.isTypeInferred()) {
         JSType type = var.getType();
         if (type == null || type.isUnknownType()) {

src/com/google/javascript/jscomp/MakeDeclaredNamesUnique.java

@@ -29,7 +29,6 @@
 import java.util.Deque;
 import java.util.HashMap;
 import java.util.HashSet;
-import java.util.Iterator;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
@@ -329,8 +328,7 @@ public void exitScope(NodeTraversal t) {
         return;
       }
 
-      for (Iterator<Var> it = t.getScope().getVars(); it.hasNext();) {
-        Var v = it.next();
+      for (Var v : t.getScope().getVarIterable()) {
         handleScopeVar(v);
       }
 

src/com/google/javascript/jscomp/MustBeReachingVariableDef.java

@@ -26,7 +26,6 @@
 
 import java.util.HashMap;
 import java.util.HashSet;
-import java.util.Iterator;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Set;
@@ -126,10 +125,9 @@ public MustDef() {
       reachingDef = new HashMap<>();
     }
 
-    public MustDef(Iterator<Var> vars) {
+    public MustDef(Iterable<? extends Var> vars) {
       this();
-      while (vars.hasNext()) {
-        Var var = vars.next();
+      for (Var var : vars) {
         // Every variable in the scope is defined once in the beginning of the
         // function: all the declared variables are undefined, all functions
         // have been assigned and all arguments has its value from the caller.
@@ -209,7 +207,7 @@ boolean isForward() {
 
   @Override
   MustDef createEntryLattice() {
-    return new MustDef(jsScope.getVars());
+    return new MustDef(jsScope.getVarIterable());
   }
 
   @Override
@@ -370,8 +368,7 @@ private void addToDefIfLocal(String name, @Nullable Node node,
   }
 
   private void escapeParameters(MustDef output) {
-    for (Iterator<Var> i = jsScope.getVars(); i.hasNext();) {
-      Var v = i.next();
+    for (Var v : jsScope.getVarIterable()) {
       if (isParameter(v)) {
         // Assume we no longer know where the parameter comes from
         // anymore.

src/com/google/javascript/jscomp/PureFunctionIdentifier.java

@@ -43,7 +43,6 @@
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
-import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -533,9 +532,7 @@ public void exitScope(NodeTraversal t) {
         return;
       }
 
-      for (Iterator<Var> i = t.getScope().getVars(); i.hasNext();) {
-        Var v = i.next();
-
+      for (Var v : t.getScope().getVarIterable()) {
         boolean param = v.getParentNode().isParamList();
         if (param &&
             !sideEffectInfo.blacklisted().contains(v) &&

src/com/google/javascript/jscomp/RemoveUnusedVars.java

@@ -29,7 +29,6 @@
 import java.util.Collection;
 import java.util.HashMap;
 import java.util.HashSet;
-import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -367,8 +366,7 @@ private void traverseFunction(Node n, Scope parentScope) {
    * for yet, add it to the list of variables to check later.
    */
   private void collectMaybeUnreferencedVars(Scope scope) {
-    for (Iterator<Var> it = scope.getVars(); it.hasNext(); ) {
-      Var var = it.next();
+    for (Var var : scope.getVarIterable()) {
       if (isRemovableVar(var)) {
         maybeUnreferenced.add(var);
       }

src/com/google/javascript/jscomp/RenameVars.java

@@ -29,7 +29,6 @@
 import java.util.Comparator;
 import java.util.HashMap;
 import java.util.HashSet;
-import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -216,9 +215,7 @@ public void enterScope(NodeTraversal t) {
         return;
       }
       Scope scope = t.getScope();
-      Iterator<Var> it = scope.getVars();
-      while (it.hasNext()) {
-        Var current = it.next();
+      for (Var current : scope.getVarIterable()) {
         if (current.isBleedingFunction()) {
           localBleedingFunctions.add(current);
           localBleedingFunctionsPerScope.put(

src/com/google/javascript/jscomp/Scope.java

@@ -21,7 +21,6 @@
 import com.google.javascript.rhino.StaticScope;
 
 import java.util.Collections;
-import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.Map;
 
@@ -190,21 +189,11 @@ public boolean isDeclared(String name, boolean recurse) {
     }
   }
 
-  /**
-   * Return an iterator over all of the variables declared in this scope.
-   */
-  @SuppressWarnings("unchecked")
-  // Untyped scopes always only contain untyped vars; getVars is polymorphic
-  // so that TypedScope#getVars can return Iterator<TypedVar>.
-  public <T extends Var> Iterator<T> getVars() {
-    return (Iterator<T>) vars.values().iterator();
-  }
-
   /**
    * Return an iterable over all of the variables declared in this scope
    * (except the special 'arguments' variable).
    */
-  Iterable<Var> getVarIterable() {
+  public Iterable<? extends Var> getVarIterable() {
     return vars.values();
   }
 

src/com/google/javascript/jscomp/ShadowVariables.java

@@ -24,7 +24,6 @@
 import com.google.javascript.rhino.Node;
 
 import java.util.Collection;
-import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.SortedSet;
@@ -182,9 +181,7 @@ public void enterScope(NodeTraversal t) {
         return;
       }
 
-      for (Iterator<Var> vars = s.getVars(); vars.hasNext();) {
-        Var var = vars.next();
-
+      for (Var var : s.getVarIterable()) {
         // Don't shadow variables that is bleed-out to fix an IE bug.
         if (var.isBleedingFunction()) {
           continue;

src/com/google/javascript/jscomp/TypeInference.java

@@ -106,10 +106,7 @@ class TypeInference
 
     // For each local variable declared with the VAR keyword, the entry
     // type is VOID.
-    Iterator<TypedVar> varIt =
-        functionScope.getDeclarativelyUnboundVarsWithoutTypes();
-    while (varIt.hasNext()) {
-      TypedVar var = varIt.next();
+    for (TypedVar var : functionScope.getDeclarativelyUnboundVarsWithoutTypes()) {
       if (isUnflowable(var)) {
         continue;
       }

src/com/google/javascript/jscomp/TypedScope.java

@@ -18,14 +18,13 @@
 
 import com.google.common.base.Preconditions;
 import com.google.common.base.Predicate;
-import com.google.common.collect.Iterators;
+import com.google.common.collect.Iterables;
 import com.google.javascript.rhino.Node;
 import com.google.javascript.rhino.jstype.JSType;
 import com.google.javascript.rhino.jstype.ObjectType;
 import com.google.javascript.rhino.jstype.StaticTypedScope;
 
 import java.util.Collections;
-import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.Map;
 
@@ -144,6 +143,7 @@ public JSType getTypeOfThis() {
     }
   }
 
+  @Override
   Var declare(String name, Node nameNode, CompilerInput input) {
     throw new IllegalStateException(
         "Method declare(untyped) cannot be called on typed scopes.");
@@ -193,6 +193,7 @@ public TypedVar getVar(String name) {
     return null;
   }
 
+  @Override
   public Var getArgumentsVar() {
     throw new IllegalStateException("Method getArgumentsVar cannot be called on typed scopes.");
   }
@@ -213,12 +214,8 @@ public boolean isDeclared(String name, boolean recurse) {
   }
 
   @Override
-  public Iterator<TypedVar> getVars() {
-    return vars.values().iterator();
-  }
-
-  Iterable<Var> getVarIterable() {
-    throw new IllegalStateException("Method getVarIterable cannot be called on typed scopes.");
+  public Iterable<TypedVar> getVarIterable() {
+    return vars.values();
   }
 
   @Override
@@ -241,8 +238,8 @@ public boolean isLocal() {
     return parent != null;
   }
 
-  public Iterator<TypedVar> getDeclarativelyUnboundVarsWithoutTypes() {
-    return Iterators.filter(getVars(), DECLARATIVELY_UNBOUND_VARS_WITHOUT_TYPES);
+  public Iterable<TypedVar> getDeclarativelyUnboundVarsWithoutTypes() {
+    return Iterables.filter(getVarIterable(), DECLARATIVELY_UNBOUND_VARS_WITHOUT_TYPES);
   }
 
   static interface TypeResolver {
@@ -263,16 +260,19 @@ void setTypeResolver(TypeResolver resolver) {
     this.typeResolver = resolver;
   }
 
+  @Override
   public boolean isBlockScope() {
     // TypedScope is not ES6 compatible yet, so always return false for now.
     return false;
   }
 
+  @Override
   public boolean isFunctionBlockScope() {
     throw new IllegalStateException(
         "Method isFunctionBlockScope cannot be called on typed scopes.");
   }
 
+  @Override
   public Scope getClosestHoistScope() {
     throw new IllegalStateException(
         "Method getClosestHoistScope cannot be called on typed scopes.");