Revert "Remove deque & limit analysis passes"

This reverts commit 821e0c5.

Author: Mikhail Arkhipov

src/Analysis/Engine/Impl/AnalysisLog.cs

@@ -15,7 +15,6 @@
 // permissions and limitations under the License.
 
 using System;
-using System.Collections.Generic;
 using Microsoft.PythonTools.Analysis.Values;
 
 namespace Microsoft.PythonTools.Analysis {
@@ -77,13 +76,13 @@ public static void Reset() {
             LastDisplayedTime = null;
         }
 
-        public static void Enqueue(Queue<AnalysisUnit> deque, AnalysisUnit unit) {
+        public static void Enqueue(Deque<AnalysisUnit> deque, AnalysisUnit unit) {
             if (Active) {
                 Add("E", IdDispenser.GetId(unit), deque.Count);
             }
         }
 
-        public static void Dequeue(Queue<AnalysisUnit> deque, AnalysisUnit unit) {
+        public static void Dequeue(Deque<AnalysisUnit> deque, AnalysisUnit unit) {
             if (Active) {
                 Add("D", IdDispenser.GetId(unit), deque.Count);
             }
@@ -109,7 +108,7 @@ public static void ExceedsTypeLimit(string variableDefType, int total, string co
             Add("X", variableDefType, total, contents);
         }
 
-        public static void Cancelled(Queue<AnalysisUnit> queue) {
+        public static void Cancelled(Deque<AnalysisUnit> queue) {
             Add("Cancel", queue.Count);
         }
 

src/Analysis/Engine/Impl/AnalysisUnit.cs

@@ -109,7 +109,7 @@ public AnalysisUnit CopyForEval() {
         }
 
         internal void Enqueue() {
-            if (!ForEval && !IsInQueue && !_suppressEnqueue && NeedsAnalysis()) {
+            if (!ForEval && !IsInQueue && !_suppressEnqueue) {
                 State.Queue.Append(this);
                 AnalysisLog.Enqueue(State.Queue, this);
                 IsInQueue = true;
@@ -120,10 +120,6 @@ internal void Enqueue() {
             }
         }
 
-        private bool NeedsAnalysis()
-            => _analysisCount == 0 || _scope != null && _scope.AllVariables.Select(k => k.Value).Any(v => !v.HasTypes);
-
-
         /// <summary>
         /// The AST which will be analyzed when this node is analyzed
         /// </summary>
@@ -365,7 +361,8 @@ public ClassAnalysisUnit(ClassDefinition node, InterpreterScope declScope, Analy
         public new ClassDefinition Ast => (ClassDefinition)base.Ast;
 
         internal override void AnalyzeWorker(DDG ddg, CancellationToken cancel) {
-            if (!ddg.Scope.TryGetNodeScope(Ast, out var scope)) {
+            InterpreterScope scope;
+            if (!ddg.Scope.TryGetNodeScope(Ast, out scope)) {
                 return;
             }
 
@@ -421,7 +418,8 @@ private IAnalysisSet ProcessClassDecorators(DDG ddg, ClassInfo classInfo) {
                 foreach (var d in Ast.Decorators.Decorators.ExcludeDefault()) {
                     var decorator = ddg._eval.Evaluate(d);
 
-                    if (!_decoratorCalls.TryGetValue(d, out var nextExpr)) {
+                    Expression nextExpr;
+                    if (!_decoratorCalls.TryGetValue(d, out nextExpr)) {
                         nextExpr = _decoratorCalls[d] = new CallExpression(d, new[] { new Arg(expr) });
                         nextExpr.SetLoc(d.IndexSpan);
                     }

src/Analysis/Engine/Impl/Analyzer/DDG.cs

@@ -30,7 +30,7 @@ internal class DDG : PythonWalker {
         private SuiteStatement _curSuite;
         public readonly HashSet<IPythonProjectEntry> AnalyzedEntries = new HashSet<IPythonProjectEntry>();
 
-        public void Analyze(Queue<AnalysisUnit> queue, CancellationToken cancel, Action<int> reportQueueSize = null, int reportQueueInterval = 1) {
+        public void Analyze(Deque<AnalysisUnit> queue, CancellationToken cancel, Action<int> reportQueueSize = null, int reportQueueInterval = 1) {
             if (cancel.IsCancellationRequested) {
                 return;
             }
@@ -46,7 +46,7 @@ public void Analyze(Queue<AnalysisUnit> queue, CancellationToken cancel, Action<
                 }
 
                 while (queue.Count > 0 && !cancel.IsCancellationRequested) {
-                    _unit = queue.Dequeue();
+                    _unit = queue.PopLeft();
 
                     if (_unit == endOfQueueMarker) {
                         AnalysisLog.EndOfQueue(queueCountAtStart, queue.Count);
@@ -107,9 +107,10 @@ public InterpreterScope Scope {
         public PythonAnalyzer ProjectState => _unit.State;
 
         public override bool Walk(PythonAst node) {
+            ModuleReference existingRef;
             Debug.Assert(node == _unit.Ast);
 
-            if (!ProjectState.Modules.TryImport(_unit.DeclaringModule.Name, out var existingRef)) {
+            if (!ProjectState.Modules.TryImport(_unit.DeclaringModule.Name, out existingRef)) {
                 // publish our module ref now so that we don't collect dependencies as we'll be fully processed
                 if (existingRef == null) {
                     ProjectState.Modules[_unit.DeclaringModule.Name] = new ModuleReference(_unit.DeclaringModule, _unit.DeclaringModule.Name);
@@ -470,7 +471,8 @@ internal List<AnalysisValue> LookupBaseMethods(string name, IEnumerable<IAnalysi
         }
 
         public override bool Walk(FunctionDefinition node) {
-            if (_unit.InterpreterScope.TryGetNodeScope(node, out var funcScope)) {
+            InterpreterScope funcScope;
+            if (_unit.InterpreterScope.TryGetNodeScope(node, out funcScope)) {
                 var function = ((FunctionScope)funcScope).Function;
                 var analysisUnit = (FunctionAnalysisUnit)((FunctionScope)funcScope).Function.AnalysisUnit;
 
@@ -630,7 +632,8 @@ public override bool Walk(AssertStatement node) {
         }
 
         private void TryPushIsInstanceScope(Node node, Expression test) {
-            if (Scope.TryGetNodeScope(node, out var newScope)) {
+            InterpreterScope newScope;
+            if (Scope.TryGetNodeScope(node, out newScope)) {
                 var outerScope = Scope;
                 var isInstanceScope = (IsInstanceScope)newScope;
 

src/Analysis/Engine/Impl/Analyzer/DependentKeyValue.cs

@@ -51,11 +51,13 @@ public bool AddTypes(IProjectEntry projectEntry, PythonAnalyzer projectState, IE
 
             bool anyAdded = false;
             foreach (var key in keyTypes) {
-                if (!dependencies.KeyValues.TryGetValue(key, out var values)) {
+                IAnalysisSet values;
+                if (!dependencies.KeyValues.TryGetValue(key, out values)) {
                     values = AnalysisSet.Create(valueTypes);
                     anyAdded = true;
                 } else {
-                    values = values.Union(valueTypes, out var added);
+                    bool added;
+                    values = values.Union(valueTypes, out added);
                     anyAdded |= added;
                 }
                 if (anyAdded && values.Count > projectState.Limits.DictValueTypes) {
@@ -161,7 +163,8 @@ public Dictionary<AnalysisValue, IAnalysisSet> KeyValueTypes {
                             }
                         } else {
                             foreach (var keyValue in mod.KeyValues) {
-                                if (!res.TryGetValue(keyValue.Key, out var existing)) {
+                                IAnalysisSet existing;
+                                if (!res.TryGetValue(keyValue.Key, out existing)) {
                                     res[keyValue.Key] = keyValue.Value;
                                 } else {
                                     res[keyValue.Key] = existing.Union(keyValue.Value, canMutate: false);
@@ -191,11 +194,13 @@ internal bool CopyFrom(DependentKeyValue dependentKeyValue, bool enqueue = true)
                 }
 
                 foreach (var keyValue in otherDependency.Value.KeyValues) {
-                    if (!deps.KeyValues.TryGetValue(keyValue.Key, out var union)) {
+                    IAnalysisSet union;
+                    if (!deps.KeyValues.TryGetValue(keyValue.Key, out union)) {
                         deps.KeyValues[keyValue.Key] = union = keyValue.Value;
                         anyAdded = true;
                     } else {
-                        deps.KeyValues[keyValue.Key] = union.Union(keyValue.Value, out var added, canMutate: false);
+                        bool added;
+                        deps.KeyValues[keyValue.Key] = union.Union(keyValue.Value, out added, canMutate: false);
                         anyAdded |= added;
                     }
                 }