Cleanup, and move to more strict contracts.

src/Features/Core/Portable/CodeFixes/Qualify/AbstractFullyQualifyCodeFixProvider.cs

@@ -140,16 +140,18 @@ private async Task<Document> ProcessNode(Document document, SyntaxNode node, str
             var syntaxFacts = project.LanguageServices.GetService<ISyntaxFactsService>();
             syntaxFacts.GetNameAndArityOfSimpleName(node, out var name, out var arity);
 
-            var symbolAndProjectIds = await DeclarationFinder.FindAllDeclarationsAsync(
-                project, name, this.IgnoreCase, SymbolFilter.Type, cancellationToken).ConfigureAwait(false);
+            var symbolAndProjectIds = await DeclarationFinder.FindAllDeclarationsWithNormalQueryAsync(
+                project, SearchQuery.Create(name, this.IgnoreCase),
+                SymbolFilter.Type, cancellationToken).ConfigureAwait(false);
             var symbols = symbolAndProjectIds.SelectAsArray(t => t.Symbol);
 
             // also lookup type symbols with the "Attribute" suffix.
             var inAttributeContext = syntaxFacts.IsAttributeName(node);
             if (inAttributeContext)
             {
-                var attributeSymbolAndProjectIds = await DeclarationFinder.FindAllDeclarationsAsync(
-                    project, name + "Attribute", this.IgnoreCase, SymbolFilter.Type, cancellationToken).ConfigureAwait(false);
+                var attributeSymbolAndProjectIds = await DeclarationFinder.FindAllDeclarationsWithNormalQueryAsync(
+                    project, SearchQuery.Create(name + "Attribute", this.IgnoreCase),
+                    SymbolFilter.Type, cancellationToken).ConfigureAwait(false);
                 symbols = symbols.Concat(attributeSymbolAndProjectIds.SelectAsArray(t => t.Symbol));
             }
 
@@ -189,8 +191,9 @@ private static bool HasValidContainer(ISymbol symbol)
                 return ImmutableArray<SymbolResult>.Empty;
             }
 
-            var symbolAndProjectIds = await DeclarationFinder.FindAllDeclarationsAsync(
-                project, name, this.IgnoreCase, SymbolFilter.Namespace, cancellationToken).ConfigureAwait(false);
+            var symbolAndProjectIds = await DeclarationFinder.FindAllDeclarationsWithNormalQueryAsync(
+                project, SearchQuery.Create(name, this.IgnoreCase), 
+                SymbolFilter.Namespace, cancellationToken).ConfigureAwait(false);
 
             var symbols = symbolAndProjectIds.SelectAsArray(t => t.Symbol);
 

src/Workspaces/Core/Portable/FindSymbols/Declarations/DeclarationFinder.cs

@@ -7,6 +7,7 @@
 using System.Threading.Tasks;
 using Microsoft.CodeAnalysis.Internal.Log;
 using Microsoft.CodeAnalysis.Shared.Extensions;
+using Roslyn.Utilities;
 
 namespace Microsoft.CodeAnalysis.FindSymbols
 {
@@ -16,7 +17,7 @@ internal static partial class DeclarationFinder
             Project project, SearchQuery query, SymbolFilter filter,
             ArrayBuilder<SymbolAndProjectId> list, CancellationToken cancellationToken)
         {
-            Debug.Assert(query.Kind != SearchKind.Custom);
+            Contract.ThrowIfTrue(query.Kind == SearchKind.Custom, "Custom queries are not supported in this API");
             return AddCompilationDeclarationsWithNormalQueryAsync(
                 project, query, filter, list,
                 startingCompilation: null,
@@ -33,7 +34,7 @@ internal static partial class DeclarationFinder
             IAssemblySymbol startingAssembly,
             CancellationToken cancellationToken)
         {
-            Debug.Assert(query.Kind != SearchKind.Custom);
+            Contract.ThrowIfTrue(query.Kind == SearchKind.Custom, "Custom queries are not supported in this API");
 
             using (Logger.LogBlock(FunctionId.SymbolFinder_Project_AddDeclarationsAsync, cancellationToken))
             {
@@ -67,7 +68,7 @@ internal static partial class DeclarationFinder
         {
             // All entrypoints to this function are Find functions that are only searching
             // for specific strings (i.e. they never do a custom search).
-            Debug.Assert(query.Kind != SearchKind.Custom);
+            Contract.ThrowIfTrue(query.Kind == SearchKind.Custom, "Custom queries are not supported in this API");
 
             using (Logger.LogBlock(FunctionId.SymbolFinder_Assembly_AddDeclarationsAsync, cancellationToken))
             {

src/Workspaces/Core/Portable/FindSymbols/Declarations/DeclarationFinder_AllDeclarations.cs

 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
 using System;
-using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Diagnostics;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.CodeAnalysis.Internal.Log;
 using Microsoft.CodeAnalysis.Remote;
 using Microsoft.CodeAnalysis.Shared.Extensions;
 using Roslyn.Utilities;
@@ -18,52 +16,12 @@ namespace Microsoft.CodeAnalysis.FindSymbols
 
     internal static partial class DeclarationFinder
     {
-        /// <summary>
-        /// Find the declared symbols from either source, referenced projects or metadata assemblies with the specified name.
-        /// </summary>
-        internal static async Task<ImmutableArray<SymbolAndProjectId>> FindAllDeclarationsAsync(
-            Project project, string name, bool ignoreCase, CancellationToken cancellationToken)
-        {
-            if (name == null)
-            {
-                throw new ArgumentNullException(nameof(name));
-            }
-
-            if (string.IsNullOrWhiteSpace(name))
-            {
-                return ImmutableArray<SymbolAndProjectId>.Empty;
-            }
-
-            return await FindAllDeclarationsWithNormalQueryAsync(
-                project, SearchQuery.Create(name, ignoreCase), SymbolFilter.All, cancellationToken: cancellationToken).ConfigureAwait(false);
-        }
-
-        /// <summary>
-        /// Find the declared symbols from either source, referenced projects or metadata assemblies with the specified name.
-        /// </summary>
-        internal static async Task<ImmutableArray<SymbolAndProjectId>> FindAllDeclarationsAsync(
-            Project project, string name, bool ignoreCase, SymbolFilter filter, CancellationToken cancellationToken = default(CancellationToken))
-        {
-            if (name == null)
-            {
-                throw new ArgumentNullException(nameof(name));
-            }
-
-            if (string.IsNullOrWhiteSpace(name))
-            {
-                return ImmutableArray<SymbolAndProjectId>.Empty;
-            }
-
-            return await FindAllDeclarationsWithNormalQueryAsync(
-                project, SearchQuery.Create(name, ignoreCase), filter, cancellationToken: cancellationToken).ConfigureAwait(false);
-        }
-
-        internal static async Task<ImmutableArray<SymbolAndProjectId>> FindAllDeclarationsWithNormalQueryAsync(
+        public static async Task<ImmutableArray<SymbolAndProjectId>> FindAllDeclarationsWithNormalQueryAsync(
             Project project, SearchQuery query, SymbolFilter criteria, CancellationToken cancellationToken)
         {
             // All entrypoints to this function are Find functions that are only searching
             // for specific strings (i.e. they never do a custom search).
-            Debug.Assert(query.Kind != SearchKind.Custom);
+            Contract.ThrowIfTrue(query.Kind == SearchKind.Custom, "Custom queries are not supported in this API");
 
             if (project == null)
             {

src/Workspaces/Core/Portable/FindSymbols/SymbolFinder_Declarations_AllDeclarations.cs

 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
-using System;
 using System.Collections.Generic;
-using System.Collections.Immutable;
-using System.Diagnostics;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.CodeAnalysis.Internal.Log;
-using Microsoft.CodeAnalysis.Shared.Extensions;
-using Roslyn.Utilities;
 
 namespace Microsoft.CodeAnalysis.FindSymbols
 {
@@ -20,8 +14,8 @@ public static partial class SymbolFinder
         public static async Task<IEnumerable<ISymbol>> FindDeclarationsAsync(
             Project project, string name, bool ignoreCase, CancellationToken cancellationToken = default(CancellationToken))
         {
-            var declarations = await DeclarationFinder.FindAllDeclarationsAsync(
-                project, name, ignoreCase, cancellationToken).ConfigureAwait(false);
+            var declarations = await DeclarationFinder.FindAllDeclarationsWithNormalQueryAsync(
+                project, SearchQuery.Create(name, ignoreCase), SymbolFilter.All, cancellationToken).ConfigureAwait(false);
             return declarations.SelectAsArray(t => t.Symbol);
         }
 
@@ -31,8 +25,8 @@ public static partial class SymbolFinder
         public static async Task<IEnumerable<ISymbol>> FindDeclarationsAsync(
             Project project, string name, bool ignoreCase, SymbolFilter filter, CancellationToken cancellationToken = default(CancellationToken))
         {
-            var declarations = await DeclarationFinder.FindAllDeclarationsAsync(
-                project, name, ignoreCase, filter, cancellationToken).ConfigureAwait(false);
+            var declarations = await DeclarationFinder.FindAllDeclarationsWithNormalQueryAsync(
+                project, SearchQuery.Create(name, ignoreCase), filter, cancellationToken).ConfigureAwait(false);
             return declarations.SelectAsArray(t => t.Symbol);
         }
     }

src/Workspaces/Core/Portable/FindSymbols/SymbolTree/SymbolTreeInfo.cs

@@ -119,7 +119,7 @@ internal partial class SymbolTreeInfo
         {
             // All entrypoints to this function are Find functions that are only searching
             // for specific strings (i.e. they never do a custom search).
-            Debug.Assert(query.Kind != SearchKind.Custom);
+            Contract.ThrowIfTrue(query.Kind == SearchKind.Custom, "Custom queries are not supported in this API");
 
             return this.FindAsync(
                 query, new AsyncLazy<IAssemblySymbol>(assembly),
@@ -132,7 +132,7 @@ internal partial class SymbolTreeInfo
         {
             // All entrypoints to this function are Find functions that are only searching
             // for specific strings (i.e. they never do a custom search).
-            Debug.Assert(query.Kind != SearchKind.Custom);
+            Contract.ThrowIfTrue(query.Kind == SearchKind.Custom, "Custom queries are not supported in this API");
 
             var symbols = await FindAsyncWorker(query, lazyAssembly, cancellationToken).ConfigureAwait(false);
 
@@ -146,7 +146,7 @@ internal partial class SymbolTreeInfo
         {
             // All entrypoints to this function are Find functions that are only searching
             // for specific strings (i.e. they never do a custom search).
-            Debug.Assert(query.Kind != SearchKind.Custom);
+            Contract.ThrowIfTrue(query.Kind == SearchKind.Custom, "Custom queries are not supported in this API");
 
             // If the query has a specific string provided, then call into the SymbolTreeInfo
             // helpers optimized for lookup based on an exact name.