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C#: Default parameter values are maybe null

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C#: Update test output
This commit is contained in:
Calum Grant
2020-01-20 13:12:27 +00:00
parent 631b4248b5
commit 9d7c9e0ba4
4 changed files with 22 additions and 6 deletions
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14
csharp/ql/src/semmle/code/csharp/dataflow/Nullness.qll
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@@ -176,7 +176,17 @@ private predicate isMaybeNullArgument(Ssa::ExplicitDefinition def, MaybeNullExpr
pdef = def.getADefinition()
|
p = pdef.getParameter().getSourceDeclaration() and
p.getAnAssignedArgument() = arg and
arg = p.getAnAssignedArgument() and
not arg.getEnclosingCallable().getEnclosingCallable*() instanceof TestMethod
)
}
private predicate isNullDefaultArgument(Ssa::ExplicitDefinition def, MaybeNullExpr arg) {
exists(AssignableDefinitions::ImplicitParameterDefinition pdef, Parameter p |
pdef = def.getADefinition()
|
p = pdef.getParameter().getSourceDeclaration() and
arg = p.getDefaultValue() and
not arg.getEnclosingCallable().getEnclosingCallable*() instanceof TestMethod
)
}
@@ -204,6 +214,8 @@ private predicate defMaybeNull(Ssa::Definition def, string msg, Element reason)
else msg = "because of $@ potential null argument"
)
or
isNullDefaultArgument(def, reason) and msg = "because the parameter has a null default value"
or
// If the source of a variable is `null` then the variable may be `null`
exists(AssignableDefinition adef | adef = def.(Ssa::ExplicitDefinition).getADefinition() |
adef.getSource() instanceof MaybeNullExpr and

2
csharp/ql/test/query-tests/Nullness/E.cs
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@@ -363,7 +363,7 @@ public class E
x.ToString(); // GOOD
}
static int Ex34(string s = null) => s.Length; // BAD (maybe) False negative
static int Ex34(string s = null) => s.Length; // BAD (maybe)
}
public static class Extensions

8
csharp/ql/test/query-tests/Nullness/Implications.expected
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@@ -1130,10 +1130,10 @@
| E.cs:199:9:199:9 | access to local variable o | non-empty | E.cs:198:17:198:29 | ... ? ... : ... | non-empty |
| E.cs:199:9:199:9 | access to local variable o | non-null | E.cs:198:17:198:29 | ... ? ... : ... | non-null |
| E.cs:199:9:199:9 | access to local variable o | null | E.cs:198:17:198:29 | ... ? ... : ... | null |
| E.cs:201:11:201:11 | access to local variable o | non-null | E.cs:198:17:198:29 | ... ? ... : ... | non-null |
| E.cs:201:11:201:11 | access to local variable o | null | E.cs:198:17:198:29 | ... ? ... : ... | null |
| E.cs:203:11:203:11 | access to local variable o | non-null | E.cs:198:17:198:29 | ... ? ... : ... | non-null |
| E.cs:203:11:203:11 | access to local variable o | null | E.cs:198:17:198:29 | ... ? ... : ... | null |
| E.cs:201:13:201:13 | access to local variable o | non-null | E.cs:198:17:198:29 | ... ? ... : ... | non-null |
| E.cs:201:13:201:13 | access to local variable o | null | E.cs:198:17:198:29 | ... ? ... : ... | null |
| E.cs:203:13:203:13 | access to local variable o | non-null | E.cs:198:17:198:29 | ... ? ... : ... | non-null |
| E.cs:203:13:203:13 | access to local variable o | null | E.cs:198:17:198:29 | ... ? ... : ... | null |
| E.cs:208:13:208:23 | ... is ... | false | E.cs:208:13:208:13 | access to parameter s | null |
| E.cs:208:13:208:23 | ... is ... | true | E.cs:208:13:208:13 | access to parameter s | non-null |
| E.cs:220:13:220:13 | access to local variable x | non-null | E.cs:217:17:217:20 | null | non-null |

4
csharp/ql/test/query-tests/Nullness/NullMaybe.expected
View File

@@ -351,6 +351,8 @@ nodes
| E.cs:343:9:343:9 | access to local variable x |
| E.cs:348:17:348:36 | SSA def(x) |
| E.cs:349:9:349:9 | access to local variable x |
| E.cs:366:28:366:28 | SSA param(s) |
| E.cs:366:41:366:41 | access to parameter s |
| Forwarding.cs:7:16:7:23 | SSA def(s) |
| Forwarding.cs:14:9:17:9 | if (...) ... |
| Forwarding.cs:19:9:22:9 | if (...) ... |
@@ -682,6 +684,7 @@ edges
| E.cs:330:13:330:36 | SSA def(x) | E.cs:331:9:331:9 | access to local variable x |
| E.cs:342:13:342:32 | SSA def(x) | E.cs:343:9:343:9 | access to local variable x |
| E.cs:348:17:348:36 | SSA def(x) | E.cs:349:9:349:9 | access to local variable x |
| E.cs:366:28:366:28 | SSA param(s) | E.cs:366:41:366:41 | access to parameter s |
| Forwarding.cs:7:16:7:23 | SSA def(s) | Forwarding.cs:14:9:17:9 | if (...) ... |
| Forwarding.cs:14:9:17:9 | if (...) ... | Forwarding.cs:19:9:22:9 | if (...) ... |
| Forwarding.cs:19:9:22:9 | if (...) ... | Forwarding.cs:24:9:27:9 | if (...) ... |
@@ -782,6 +785,7 @@ edges
| E.cs:302:9:302:9 | access to local variable s | E.cs:301:13:301:27 | SSA def(s) | E.cs:302:9:302:9 | access to local variable s | Variable $@ may be null here because of $@ assignment. | E.cs:301:13:301:13 | s | s | E.cs:301:13:301:27 | String s = ... | this |
| E.cs:343:9:343:9 | access to local variable x | E.cs:342:13:342:32 | SSA def(x) | E.cs:343:9:343:9 | access to local variable x | Variable $@ may be null here because of $@ assignment. | E.cs:342:13:342:13 | x | x | E.cs:342:13:342:32 | String x = ... | this |
| E.cs:349:9:349:9 | access to local variable x | E.cs:348:17:348:36 | SSA def(x) | E.cs:349:9:349:9 | access to local variable x | Variable $@ may be null here because of $@ assignment. | E.cs:348:17:348:17 | x | x | E.cs:348:17:348:36 | dynamic x = ... | this |
| E.cs:366:41:366:41 | access to parameter s | E.cs:366:28:366:28 | SSA param(s) | E.cs:366:41:366:41 | access to parameter s | Variable $@ may be null here because the parameter has a null default value. | E.cs:366:28:366:28 | s | s | E.cs:366:32:366:35 | null | this |
| GuardedString.cs:35:31:35:31 | access to local variable s | GuardedString.cs:7:16:7:32 | SSA def(s) | GuardedString.cs:35:31:35:31 | access to local variable s | Variable $@ may be null here because of $@ assignment. | GuardedString.cs:7:16:7:16 | s | s | GuardedString.cs:7:16:7:32 | String s = ... | this |
| NullMaybeBad.cs:7:27:7:27 | access to parameter o | NullMaybeBad.cs:13:17:13:20 | null | NullMaybeBad.cs:7:27:7:27 | access to parameter o | Variable $@ may be null here because of $@ null argument. | NullMaybeBad.cs:5:25:5:25 | o | o | NullMaybeBad.cs:13:17:13:20 | null | this |
| StringConcatenation.cs:16:17:16:17 | access to local variable s | StringConcatenation.cs:14:16:14:23 | SSA def(s) | StringConcatenation.cs:16:17:16:17 | access to local variable s | Variable $@ may be null here because of $@ assignment. | StringConcatenation.cs:14:16:14:16 | s | s | StringConcatenation.cs:14:16:14:23 | String s = ... | this |