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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
using System;
using System.Diagnostics.CodeAnalysis;
using Mono.Linker.Tests.Cases.Expectations.Assertions;
using Mono.Linker.Tests.Cases.Expectations.Helpers;
namespace Mono.Linker.Tests.Cases.DataFlow
{
// Note: this test's goal is to validate that the product correctly reports unrecognized patterns
// - so the main validation is done by the ExpectedWarning attributes.
[SkipKeptItemsValidation]
[ExpectedNoWarnings]
public class LocalDataFlow
{
public static void Main ()
{
// These behave as expected
TestBranchMergeGoto ();
TestBranchMergeIf ();
TestBranchMergeIfElse ();
TestBranchMergeSwitch ();
TestBranchMergeTry ();
TestBranchMergeCatch ();
// The remaining tests illustrate current limitations of the analysis
// that we might be able to lift in the future.
// These are overly conservative (extraneous warnings)
// https://github.com/dotnet/linker/issues/2550
TestBranchGoto ();
TestBranchIf ();
TestBranchIfElse ();
TestBranchSwitch ();
TestBranchTry ();
TestBranchCatch ();
TestBranchFinally ();
TestBranchMergeFinally ();
// These are missing warnings (potential failure at runtime)
TestBackwardsEdgeGoto ();
TestBackwardsEdgeLoop ();
TestNoWarningsInRUCMethod ();
TestNoWarningsInRUCType ();
// These are probably just bugs
TestBackwardEdgeWithLdElem ();
}
[ExpectedWarning ("IL2072",
"Mono.Linker.Tests.Cases.DataFlow.LocalDataFlow.GetWithPublicMethods()",
nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicFields) + "(String)")]
[ExpectedWarning ("IL2072",
"Mono.Linker.Tests.Cases.DataFlow.LocalDataFlow.GetWithPublicFields()",
nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicMethods) + "(String)")]
public static void TestBranchMergeGoto ()
{
string str = GetWithPublicMethods ();
if (String.Empty.Length == 0)
goto End;
str = GetWithPublicFields ();
End:
str.RequiresPublicFields (); // warns for GetWithPublicMethods
str.RequiresPublicMethods (); // warns for GetWithPublicFields
}
[ExpectedWarning ("IL2072",
"Mono.Linker.Tests.Cases.DataFlow.LocalDataFlow.GetWithPublicMethods()",
nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicFields) + "(String)")]
[ExpectedWarning ("IL2072",
"Mono.Linker.Tests.Cases.DataFlow.LocalDataFlow.GetWithPublicFields()",
nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicMethods) + "(String)")]
public static void TestBranchMergeIf ()
{
string str = GetWithPublicMethods ();
if (String.Empty.Length == 0)
str = GetWithPublicFields ();
str.RequiresPublicFields (); // warns for GetWithPublicMethods
str.RequiresPublicMethods (); // warns for GetWithPublicFields
}
[ExpectedWarning ("IL2072",
"Mono.Linker.Tests.Cases.DataFlow.LocalDataFlow.GetWithPublicMethods()",
nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicFields) + "(String)")]
[ExpectedWarning ("IL2072",
"Mono.Linker.Tests.Cases.DataFlow.LocalDataFlow.GetWithPublicFields()",
nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicMethods) + "(String)")]
public static void TestBranchMergeIfElse ()
{
string str = null;
if (String.Empty.Length == 0) {
str = GetWithPublicFields ();
} else {
str = GetWithPublicMethods ();
}
str.RequiresPublicFields (); // warns for GetWithPublicMethods
str.RequiresPublicMethods (); // warns for GetWithPublicFields
}
static int _switchOnField;
[ExpectedWarning ("IL2072",
"Mono.Linker.Tests.Cases.DataFlow.LocalDataFlow.GetWithPublicFields()",
nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresNonPublicMethods) + "(String)")]
[ExpectedWarning ("IL2072",
"Mono.Linker.Tests.Cases.DataFlow.LocalDataFlow.GetWithPublicMethods()",
nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresNonPublicMethods) + "(String)")]
[ExpectedWarning ("IL2072",
"Mono.Linker.Tests.Cases.DataFlow.LocalDataFlow.GetWithPublicConstructors()",
nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresNonPublicMethods) + "(String)")]
public static void TestBranchMergeSwitch ()
{
string str = null;
switch (_switchOnField) {
case 0:
str = GetWithPublicFields ();
break;
case 1:
str = GetWithNonPublicMethods ();
break;
case 2:
str = GetWithPublicMethods ();
break;
case 3:
str = GetWithPublicConstructors ();
break;
}
str.RequiresNonPublicMethods (); // warns for GetWithPublicFields, GetWithPublicMethods, and GetWithPublicConstructors
}
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicFields) + "(String)",
nameof (LocalDataFlow) + "." + nameof (GetWithPublicMethods) + "()")]
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicMethods) + "(String)",
nameof (LocalDataFlow) + "." + nameof (GetWithPublicFields) + "()")]
public static void TestBranchMergeTry ()
{
string str = GetWithPublicMethods ();
try {
if (String.Empty.Length == 0)
throw null;
str = GetWithPublicFields ();
} catch {
}
str.RequiresPublicFields (); // warns for GetWithPublicMethods
str.RequiresPublicMethods (); // warns for GetWithPublicFields
}
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicFields) + "(String)",
nameof (LocalDataFlow) + "." + nameof (GetWithPublicMethods) + "()")]
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicMethods) + "(String)",
nameof (LocalDataFlow) + "." + nameof (GetWithPublicFields) + "()")]
public static void TestBranchMergeCatch ()
{
string str = GetWithPublicMethods ();
try {
if (String.Empty.Length == 0)
throw null;
} catch {
str = GetWithPublicFields ();
}
str.RequiresPublicFields (); // warns for GetWithPublicMethods
str.RequiresPublicMethods (); // warns for GetWithPublicFields
}
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicMethods) + "(String)",
nameof (LocalDataFlow) + "." + nameof (GetWithPublicFields) + "()")]
// Linker produces extraneous warnings
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicFields) + "(String)",
nameof (LocalDataFlow) + "." + nameof (GetWithPublicMethods) + "()",
ProducedBy = ProducedBy.Trimmer)]
public static void TestBranchMergeFinally ()
{
string str = GetWithPublicMethods ();
try {
if (String.Empty.Length == 0)
throw null;
} catch {
} finally {
str = GetWithPublicFields ();
}
str.RequiresPublicFields (); // should not warn
str.RequiresPublicMethods (); // should warn
}
// Analyzer gets this right (no warning), but trimmer merges all branches going forward.
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicFields) + "(String)",
ProducedBy = ProducedBy.Trimmer)]
public static void TestBranchGoto ()
{
string str = GetWithPublicMethods ();
if (String.Empty.Length == 0)
goto End;
str = GetWithPublicFields ();
str.RequiresPublicFields (); // produces a warning
End:
return;
}
// Analyzer gets this right (no warning), but trimmer merges all branches going forward.
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicFields),
ProducedBy = ProducedBy.Trimmer)]
public static void TestBranchIf ()
{
string str = GetWithPublicMethods ();
if (String.Empty.Length == 0) {
str = GetWithPublicFields (); // dataflow will merge this with the value from the previous basic block
str.RequiresPublicFields (); // produces a warning (technically it should not)
}
}
// Analyzer gets this right (no warning), but trimmer merges all branches going forward.
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicFields),
ProducedBy = ProducedBy.Trimmer)]
public static void TestBranchIfElse ()
{
string str;
if (String.Empty.Length == 0) {
// because this branch *happens* to come first in IL, we will only see one value
str = GetWithPublicMethods ();
str.RequiresPublicMethods (); // this works
} else {
// because this branch *happens* to come second in IL, we will see the merged value for str
str = GetWithPublicFields ();
str.RequiresPublicFields (); // produces a warning
}
}
// Analyzer gets this right (no warning), but trimmer merges all branches going forward.
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresNonPublicMethods) + "(String)",
ProducedBy = ProducedBy.Trimmer)]
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicMethods) + "(String)",
ProducedBy = ProducedBy.Trimmer)]
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicMethods) + "(String)",
ProducedBy = ProducedBy.Trimmer)]
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicConstructors) + "(String)",
ProducedBy = ProducedBy.Trimmer)]
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicConstructors) + "(String)",
ProducedBy = ProducedBy.Trimmer)]
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicConstructors) + "(String)",
ProducedBy = ProducedBy.Trimmer)]
public static void TestBranchSwitch ()
{
string str = null;
switch (_switchOnField) {
case 0:
str = GetWithPublicFields ();
str.RequiresPublicFields (); // success
break;
case 1:
str = GetWithNonPublicMethods ();
str.RequiresNonPublicMethods (); // warns for GetWithPublicFields
break;
case 2:
str = GetWithPublicMethods ();
str.RequiresPublicMethods (); // warns for GetWithPublicFields and GetWithNonPublicMethods
break;
case 3:
str = GetWithPublicConstructors ();
str.RequiresPublicConstructors (); // warns for GetWithPublicFields, GetWithNonPublicMethods, GetWithPublicMethods
break;
}
}
// Analyzer gets this right (no warning), but trimmer merges all branches going forward.
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicFields),
nameof (LocalDataFlow) + "." + nameof (GetWithPublicMethods) + "()",
ProducedBy = ProducedBy.Trimmer)]
public static void TestBranchTry ()
{
string str = GetWithPublicMethods ();
try {
if (String.Empty.Length == 0)
throw null;
str = GetWithPublicFields ();
str.RequiresPublicFields (); // warns for GetWithPublicMethods
} catch {
}
}
// Analyzer gets this right (no warning), but trimmer merges all branches going forward.
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicFields),
nameof (LocalDataFlow) + "." + nameof (GetWithPublicMethods) + "()",
ProducedBy = ProducedBy.Trimmer)]
public static void TestBranchCatch ()
{
string str = GetWithPublicMethods ();
try {
if (String.Empty.Length == 0)
throw null;
} catch {
str = GetWithPublicFields ();
str.RequiresPublicFields (); // warns for GetWithPublicMethods
}
}
// Analyzer gets this right (no warning), but trimmer merges all branches going forward.
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicFields),
nameof (LocalDataFlow) + "." + nameof (GetWithPublicMethods) + "()",
ProducedBy = ProducedBy.Trimmer)]
public static void TestBranchFinally ()
{
string str = GetWithPublicMethods ();
try {
if (String.Empty.Length == 0)
throw null;
} catch {
} finally {
str = GetWithPublicFields ();
str.RequiresPublicFields (); // warns for GetWithPublicMethods
}
}
// Analyzer gets this right, but linker doesn't consider backwards branches.
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicMethods) + "(String)",
nameof (LocalDataFlow) + "." + nameof (GetWithPublicFields) + "()",
ProducedBy = ProducedBy.Analyzer)]
public static void TestBackwardsEdgeLoop ()
{
string str = GetWithPublicMethods ();
string prev = null;
for (int i = 0; i < 5; i++) {
prev = str; // dataflow will only consider the first reaching definition of "str" above
str = GetWithPublicFields (); // dataflow will merge values to track both possible annotation kinds
}
// str.RequiresPublicMethods (); // this would produce a warning for the value that comes from GetWithPublicFields, as expected
prev.RequiresPublicMethods (); // this produces no warning, even though "prev" will have the value from GetWithPublicFields!
}
// Analyzer gets this right, but linker doesn't consider backwards branches.
[ExpectedWarning ("IL2072", nameof (DataFlowStringExtensions) + "." + nameof (DataFlowStringExtensions.RequiresPublicMethods) + "(String)",
nameof (LocalDataFlow) + "." + nameof (GetWithPublicFields) + "()",
ProducedBy = ProducedBy.Analyzer)]
public static void TestBackwardsEdgeGoto ()
{
string str = null;
goto ForwardTarget;
BackwardTarget:
str.RequiresPublicMethods (); // should warn for the value that comes from GetWithPublicFields, but it doesn't.
return;
ForwardTarget:
str = GetWithPublicFields ();
goto BackwardTarget;
}
[ExpectedWarning ("IL2026", nameof (RUCMethod), "message")]
public static void TestNoWarningsInRUCMethod ()
{
RUCMethod ();
}
[RequiresUnreferencedCode ("message")]
public static void RUCMethod ()
{
GetWithPublicMethods ().RequiresAll ();
}
[ExpectedWarning ("IL2026", nameof (RUCType) + "." + nameof (RUCType), "message")]
[ExpectedWarning ("IL2026", nameof (RUCType.StaticMethod), "message")]
public static void TestNoWarningsInRUCType ()
{
RUCType.StaticMethod ();
var rucType = new RUCType ();
rucType.InstanceMethod ();
rucType.VirtualMethod ();
}
[RequiresUnreferencedCode ("message")]
public class RUCType
{
public static void StaticMethod ()
{
GetWithPublicMethods ().RequiresAll ();
}
public void InstanceMethod ()
{
GetWithPublicMethods ().RequiresAll ();
}
public virtual void VirtualMethod ()
{
GetWithPublicMethods ().RequiresAll ();
}
}
// https://github.com/dotnet/linker/issues/2273
// Analyzer doesn't see through foreach over array at all - will not warn
[ExpectedWarning ("IL2063", ProducedBy = ProducedBy.Trimmer)] // The types loaded from the array don't have annotations, so the "return" should warn
[return: DynamicallyAccessedMembers (DynamicallyAccessedMemberTypes.PublicMethods)]
public static Type TestBackwardEdgeWithLdElem (Type[] types = null)
{
Type resultType = null;
foreach (var type in types) {
resultType = type;
}
return resultType;
}
public static void RequireAll (
[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)]
string type)
{
}
public static void RequirePublicFields (
[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicFields)]
string type)
{
}
public static void RequireNonPublicMethods (
[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.NonPublicMethods)]
string type)
{
}
public static void RequirePublicMethods (
[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods)]
string type)
{
}
public static void RequirePublicConstructors (
[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors)]
string type)
{
}
[return: DynamicallyAccessedMembers (DynamicallyAccessedMemberTypes.PublicFields)]
public static string GetWithPublicFields ()
{
return null;
}
[return: DynamicallyAccessedMembers (DynamicallyAccessedMemberTypes.NonPublicMethods)]
public static string GetWithNonPublicMethods ()
{
return null;
}
[return: DynamicallyAccessedMembers (DynamicallyAccessedMemberTypes.PublicMethods)]
public static string GetWithPublicMethods ()
{
return null;
}
[return: DynamicallyAccessedMembers (DynamicallyAccessedMemberTypes.PublicConstructors)]
public static string GetWithPublicConstructors ()
{
return null;
}
}
}
|