From 856df7f74517aa9afcc1db69988bb5999edae7fa Mon Sep 17 00:00:00 2001
From: Sam Harwell <Sam.Harwell@microsoft.com>
Date: Thu, 17 Jun 2021 11:06:44 -0700
Subject: [PATCH] Assert non-null return values from MethodSymbol.Parameters

---
 .../Portable/Symbols/Source/SourceDelegateMethodSymbol.cs      | 3 ++-
 .../Symbols/Synthesized/SynthesizedGlobalMethodSymbol.cs       | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/Compilers/CSharp/Portable/Symbols/Source/SourceDelegateMethodSymbol.cs b/src/Compilers/CSharp/Portable/Symbols/Source/SourceDelegateMethodSymbol.cs
index b4eab31db8f74..d1282fe90152f 100644
--- a/src/Compilers/CSharp/Portable/Symbols/Source/SourceDelegateMethodSymbol.cs
+++ b/src/Compilers/CSharp/Portable/Symbols/Source/SourceDelegateMethodSymbol.cs
@@ -126,7 +126,8 @@ public sealed override ImmutableArray<ParameterSymbol> Parameters
         {
             get
             {
-                return _parameters;
+                Debug.Assert(!_parameters.IsDefault, $"Expected {nameof(InitializeParameters)} prior to accessing this property.");
+                return _parameters.NullToEmpty();
             }
         }
 
diff --git a/src/Compilers/CSharp/Portable/Symbols/Synthesized/SynthesizedGlobalMethodSymbol.cs b/src/Compilers/CSharp/Portable/Symbols/Synthesized/SynthesizedGlobalMethodSymbol.cs
index 8f7155d60dadd..4b66d9d66ebfe 100644
--- a/src/Compilers/CSharp/Portable/Symbols/Synthesized/SynthesizedGlobalMethodSymbol.cs
+++ b/src/Compilers/CSharp/Portable/Symbols/Synthesized/SynthesizedGlobalMethodSymbol.cs
@@ -167,7 +167,8 @@ public override ImmutableArray<ParameterSymbol> Parameters
         {
             get
             {
-                if (_parameters.IsEmpty)
+                Debug.Assert(!_parameters.IsDefault, $"Expected {nameof(SetParameters)} prior to accessing this property.");
+                if (_parameters.IsDefault)
                 {
                     return ImmutableArray<ParameterSymbol>.Empty;
                 }