Fixed NRE when calling CanExecute(null) over value types

Sergio0694 · Sergio0694 · commit 3f965b280c32 · 2020-12-11T13:26:40.000+01:00
diff --git a/Microsoft.Toolkit.Mvvm/Input/AsyncRelayCommand{T}.cs b/Microsoft.Toolkit.Mvvm/Input/AsyncRelayCommand{T}.cs
@@ -132,10 +132,9 @@ public bool CanExecute(T? parameter)
         public bool CanExecute(object? parameter)
         {
             if (default(T) is not null &&
-                parameter is null &&
-                this.canExecute is null)
+                parameter is null)
             {
-                return true;
+                return false;
             }
 
             return CanExecute((T?)parameter);
diff --git a/Microsoft.Toolkit.Mvvm/Input/RelayCommand{T}.cs b/Microsoft.Toolkit.Mvvm/Input/RelayCommand{T}.cs
@@ -77,10 +77,9 @@ public bool CanExecute(T? parameter)
         public bool CanExecute(object? parameter)
         {
             if (default(T) is not null &&
-                parameter is null &&
-                this.canExecute is null)
+                parameter is null)
             {
-                return true;
+                return false;
             }
 
             return CanExecute((T?)parameter);

Original file line number	Diff line number	Diff line change
`@@ -132,10 +132,9 @@ public bool CanExecute(T? parameter)`
`132`	`132`	`public bool CanExecute(object? parameter)`
`133`	`133`	`{`
`134`	`134`	`if (default(T) is not null &&`
`135`		`- parameter is null &&`
`136`		`- this.canExecute is null)`
	`135`	`+ parameter is null)`
`137`	`136`	`{`
`138`		`- return true;`
	`137`	`+ return false;`
`139`	`138`	`}`
`140`	`139`
`141`	`140`	`return CanExecute((T?)parameter);`
Original file line number	Diff line number	Diff line change
`@@ -77,10 +77,9 @@ public bool CanExecute(T? parameter)`
`77`	`77`	`public bool CanExecute(object? parameter)`
`78`	`78`	`{`
`79`	`79`	`if (default(T) is not null &&`
`80`		`- parameter is null &&`
`81`		`- this.canExecute is null)`
	`80`	`+ parameter is null)`
`82`	`81`	`{`
`83`		`- return true;`
	`82`	`+ return false;`
`84`	`83`	`}`
`85`	`84`
`86`	`85`	`return CanExecute((T?)parameter);`