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Merge pull request #21599 from aschackmull/csharp/constantcondition-simplify

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C#: Simplify the ConstantCondition query.
This commit is contained in:
Anders Schack-Mulligen
2026-03-31 11:02:30 +02:00
committed by GitHub
parent 71b38b71bf 29500c7eb7
commit 2bde364bdd
25 changed files with 109 additions and 265 deletions
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1
csharp/ql/integration-tests/posix/query-suite/csharp-code-quality-extended.qls.expected
View File

@@ -65,7 +65,6 @@ ql/csharp/ql/src/Likely Bugs/Collections/ContainerLengthCmpOffByOne.ql
ql/csharp/ql/src/Likely Bugs/Collections/ContainerSizeCmpZero.ql
ql/csharp/ql/src/Likely Bugs/Collections/ReadOnlyContainer.ql
ql/csharp/ql/src/Likely Bugs/Collections/WriteOnlyContainer.ql
ql/csharp/ql/src/Likely Bugs/ConstantComparison.ql
ql/csharp/ql/src/Likely Bugs/DangerousNonShortCircuitLogic.ql
ql/csharp/ql/src/Likely Bugs/Dynamic/BadDynamicCall.ql
ql/csharp/ql/src/Likely Bugs/EqualityCheckOnFloats.ql

1
csharp/ql/integration-tests/posix/query-suite/csharp-code-quality.qls.expected
View File

@@ -38,7 +38,6 @@ ql/csharp/ql/src/Likely Bugs/Collections/ContainerLengthCmpOffByOne.ql
ql/csharp/ql/src/Likely Bugs/Collections/ContainerSizeCmpZero.ql
ql/csharp/ql/src/Likely Bugs/Collections/ReadOnlyContainer.ql
ql/csharp/ql/src/Likely Bugs/Collections/WriteOnlyContainer.ql
ql/csharp/ql/src/Likely Bugs/ConstantComparison.ql
ql/csharp/ql/src/Likely Bugs/DangerousNonShortCircuitLogic.ql
ql/csharp/ql/src/Likely Bugs/EqualityCheckOnFloats.ql
ql/csharp/ql/src/Likely Bugs/EqualsArray.ql

1
csharp/ql/integration-tests/posix/query-suite/csharp-security-and-quality.qls.expected
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@@ -69,7 +69,6 @@ ql/csharp/ql/src/Likely Bugs/Collections/ContainerLengthCmpOffByOne.ql
ql/csharp/ql/src/Likely Bugs/Collections/ContainerSizeCmpZero.ql
ql/csharp/ql/src/Likely Bugs/Collections/ReadOnlyContainer.ql
ql/csharp/ql/src/Likely Bugs/Collections/WriteOnlyContainer.ql
ql/csharp/ql/src/Likely Bugs/ConstantComparison.ql
ql/csharp/ql/src/Likely Bugs/DangerousNonShortCircuitLogic.ql
ql/csharp/ql/src/Likely Bugs/Dynamic/BadDynamicCall.ql
ql/csharp/ql/src/Likely Bugs/EqualityCheckOnFloats.ql

13
csharp/ql/lib/semmle/code/csharp/commons/Constants.qll
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@@ -4,19 +4,6 @@ import csharp
private import semmle.code.csharp.commons.ComparisonTest
private import semmle.code.csharp.commons.StructuralComparison as StructuralComparison
pragma[noinline]
private predicate isConstantCondition0(ControlFlow::Node cfn, boolean b) {
exists(cfn.getASuccessorByType(any(ControlFlow::BooleanSuccessor t | t.getValue() = b))) and
strictcount(ControlFlow::SuccessorType t | exists(cfn.getASuccessorByType(t))) = 1
}
/**
* Holds if `e` is a condition that always evaluates to Boolean value `b`.
*/
predicate isConstantCondition(Expr e, boolean b) {
forex(ControlFlow::Node cfn | cfn = e.getAControlFlowNode() | isConstantCondition0(cfn, b))
}
/**
* Holds if comparison operation `co` is constant with the Boolean value `b`.
* For example, the comparison `x > x` is constantly `false` in

113
csharp/ql/src/Bad Practices/Control-Flow/ConstantCondition.ql
View File

@@ -41,7 +41,9 @@ module ConstCondInput implements ConstCond::InputSig<ControlFlow::BasicBlock> {
module ConstCondImpl = ConstCond::Make<Location, Cfg, ConstCondInput>;
predicate nullCheck(Expr e, boolean direct) {
exists(QualifiableExpr qe | qe.isConditional() and qe.getQualifier() = e and direct = true)
exists(QualifiableExpr qe | qe.isConditional() and direct = true |
qe.getQualifier() = e or qe.(ExtensionMethodCall).getArgument(0) = e
)
or
exists(NullCoalescingOperation nce | nce.getLeftOperand() = e and direct = true)
or
@@ -108,57 +110,14 @@ class ConstantGuard extends ConstantCondition {
class ConstantBooleanCondition extends ConstantCondition {
boolean b;
ConstantBooleanCondition() { isConstantCondition(this, b) }
ConstantBooleanCondition() { isConstantComparison(this, b) }
override string getMessage() { result = "Condition always evaluates to '" + b + "'." }
override predicate isWhiteListed() {
// E.g. `x ?? false`
this.(BoolLiteral) = any(NullCoalescingOperation nce).getRightOperand() or
// No need to flag logical operations when the operands are constant
isConstantCondition(this.(LogicalNotExpr).getOperand(), _) or
this =
any(LogicalAndExpr lae |
isConstantCondition(lae.getAnOperand(), false)
or
isConstantCondition(lae.getLeftOperand(), true) and
isConstantCondition(lae.getRightOperand(), true)
) or
this =
any(LogicalOrExpr loe |
isConstantCondition(loe.getAnOperand(), true)
or
isConstantCondition(loe.getLeftOperand(), false) and
isConstantCondition(loe.getRightOperand(), false)
)
}
}
/** A constant condition in an `if` statement or a conditional expression. */
class ConstantIfCondition extends ConstantBooleanCondition {
ConstantIfCondition() {
this = any(IfStmt is).getCondition().getAChildExpr*() or
this = any(ConditionalExpr ce).getCondition().getAChildExpr*()
}
override predicate isWhiteListed() {
ConstantBooleanCondition.super.isWhiteListed()
or
// It is a common pattern to use a local constant/constant field to control
// whether code parts must be executed or not
this instanceof AssignableRead and
not this instanceof ParameterRead
}
}
/** A constant loop condition. */
class ConstantLoopCondition extends ConstantBooleanCondition {
ConstantLoopCondition() { this = any(LoopStmt ls).getCondition() }
override predicate isWhiteListed() {
// Clearly intentional infinite loops are allowed
this.(BoolLiteral).getBoolValue() = true
}
private Expr getQualifier(QualifiableExpr e) {
// `e.getQualifier()` does not work for calls to extension methods
result = e.getChildExpr(-1)
}
/** A constant nullness condition. */
@@ -166,14 +125,23 @@ class ConstantNullnessCondition extends ConstantCondition {
boolean b;
ConstantNullnessCondition() {
forex(ControlFlow::Node cfn | cfn = this.getAControlFlowNode() |
exists(ControlFlow::NullnessSuccessor t, ControlFlow::Node s |
s = cfn.getASuccessorByType(t)
|
b = t.getValue() and
not s.isJoin()
) and
strictcount(ControlFlow::SuccessorType t | exists(cfn.getASuccessorByType(t))) = 1
nullCheck(this, true) and
exists(Expr stripped | stripped = this.(Expr).stripCasts() |
stripped.getType() =
any(ValueType t |
not t instanceof NullableType and
// Extractor bug: the type of `x?.Length` is reported as `int`, but it should
// be `int?`
not getQualifier*(stripped).(QualifiableExpr).isConditional()
) and
b = false
or
stripped instanceof NullLiteral and
b = true
or
stripped.hasValue() and
not stripped instanceof NullLiteral and
b = false
)
}
@@ -184,39 +152,6 @@ class ConstantNullnessCondition extends ConstantCondition {
}
}
/** A constant matching condition. */
class ConstantMatchingCondition extends ConstantCondition {
boolean b;
ConstantMatchingCondition() {
this instanceof Expr and
forex(ControlFlow::Node cfn | cfn = this.getAControlFlowNode() |
exists(ControlFlow::MatchingSuccessor t | exists(cfn.getASuccessorByType(t)) |
b = t.getValue()
) and
strictcount(ControlFlow::SuccessorType t | exists(cfn.getASuccessorByType(t))) = 1
)
}
override predicate isWhiteListed() {
exists(Switch se, Case c, int i |
c = se.getCase(i) and
c.getPattern() = this.(DiscardExpr)
|
i > 0
or
i = 0 and
exists(Expr cond | c.getCondition() = cond and not isConstantCondition(cond, true))
)
or
this = any(PositionalPatternExpr ppe).getPattern(_)
}
override string getMessage() {
if b = true then result = "Pattern always matches." else result = "Pattern never matches."
}
}
from ConstantCondition c, string msg, Guards::Guards::Guard reason, string reasonMsg
where
msg = c.getMessage() and

3
csharp/ql/src/CSI/CompareIdenticalValues.ql
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@@ -47,7 +47,6 @@ where
not comparesIdenticalValuesNan(ct, _) and msg = "Comparison of identical values."
) and
not isMutatingOperation(ct.getAnArgument().getAChild*()) and
not isConstantCondition(e, _) and // Avoid overlap with cs/constant-condition
not isConstantComparison(e, _) and // Avoid overlap with cs/constant-comparison
not isConstantComparison(e, _) and // Avoid overlap with cs/constant-condition
not isExprInAssertion(e)
select ct, msg

2
csharp/ql/src/Likely Bugs/ConstantComparison.cs
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@@ -1,2 +0,0 @@
for (uint order = numberOfOrders; order >= 0; order--)
ProcessOrder(order);

46
csharp/ql/src/Likely Bugs/ConstantComparison.qhelp
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@@ -1,46 +0,0 @@
<!DOCTYPE qhelp PUBLIC
"-//Semmle//qhelp//EN"
"qhelp.dtd">
<qhelp>
<overview>
<p>
Comparisons which always yield the same result are unnecessary and may indicate a bug in the
logic. This can happen when the data type of one of the operands has a limited range of values.
For example unsigned integers are always greater than or equal to zero, and <code>byte</code>
values are always less than 256.
</p>
<p>The following expressions always have the same result:</p>
<ul>
<li><code>Unsigned &lt; 0</code> is always false,</li>
<li><code>0 &gt; Unsigned</code> is always false,</li>
<li><code>0 &le; Unsigned</code> is always true,</li>
<li><code>Unsigned &ge; 0</code> is always true,</li>
<li><code>Unsigned == -1</code> is always false,</li>
<li><code>Byte &lt; 512</code> is always true.</li>
</ul>
</overview>
<recommendation>
<p>
Examine the logic of the program to determine whether the comparison is necessary.
Either change the data types, or remove the unnecessary code.
</p>
</recommendation>
<example>
<p>The following example attempts to count down from <code>numberOfOrders</code> to <code>0</code>,
however the loop never terminates because <code>order</code> is an unsigned integer and so the
condition <code>order >= 0</code> is always true.</p>
<sample src="ConstantComparison.cs"/>
<p>The solution is to change the type of the variable <code>order</code>.</p>
</example>
<references>
<li>
MSDN Library: <a href="https://msdn.microsoft.com/en-us/library/6a71f45d.aspx">C# Operators</a>.
</li>
</references>
</qhelp>

22
csharp/ql/src/Likely Bugs/ConstantComparison.ql
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@@ -1,22 +0,0 @@
/**
* @name Comparison is constant
* @description The result of the comparison is always the same.
* @kind problem
* @problem.severity warning
* @precision high
* @id cs/constant-comparison
* @tags quality
* reliability
* correctness
*/
import csharp
import semmle.code.csharp.commons.Assertions
import semmle.code.csharp.commons.Constants
from ComparisonOperation cmp, boolean value
where
isConstantComparison(cmp, value) and
not isConstantCondition(cmp, _) and // Avoid overlap with cs/constant-condition
not isExprInAssertion(cmp)
select cmp, "This comparison is always " + value + "."

4
csharp/ql/src/change-notes/2026-03-31-constantcondition-simplify.md Normal file
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@@ -0,0 +1,4 @@
---
category: majorAnalysis
---
* The `cs/constant-condition` query has been simplified. The query no longer reports trivially constant conditions as they were found to generally be intentional. As a result, it should now produce fewer false positives. Additionally, the simplification means that it now reports all the results that `cs/constant-comparison` used to report, and as consequence, that query has been deleted.

1
csharp/ql/src/codeql-suites/csharp-security-and-quality.qls
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@@ -22,7 +22,6 @@
- cs/comparison-of-identical-expressions
- cs/complex-block
- cs/complex-condition
- cs/constant-comparison
- cs/constant-condition
- cs/coupled-types
- cs/dereferenced-value-is-always-null

54
csharp/ql/test/query-tests/Likely Bugs/ConstantComparison/ConstantComparison.cs → csharp/ql/test/query-tests/Bad Practices/Control-Flow/ConstantCondition/ConstantComparison.cs
View File

@@ -16,16 +16,16 @@ class Test
{
bool good, bad;
bad = uintValue < 0;
bad = 0 > uintValue;
bad = 0 <= uintValue;
bad = uintValue >= 0;
bad = uintValue < 0; // $ Alert
bad = 0 > uintValue; // $ Alert
bad = 0 <= uintValue; // $ Alert
bad = uintValue >= 0; // $ Alert
bad = uintValue == -1;
bad = uintValue != -1;
bad = 256 == byteValue;
bad = 256 != byteValue;
bad = 1 != 0;
bad = uintValue == -1; // $ Alert
bad = uintValue != -1; // $ Alert
bad = 256 == byteValue; // $ Alert
bad = 256 != byteValue; // $ Alert
bad = 1 != 0; // $ Alert
good = byteValue == 50;
good = 50 != byteValue;
@@ -35,61 +35,61 @@ class Test
good = intValue <= 1u;
good = 1u >= intValue;
good = charValue >= '0'; // Regression
good = charValue >= '0';
good = charValue < '0';
// Test ranges
bad = charValue <= 65535;
bad = charValue >= 0;
bad = charValue <= 65535; // $ Alert
bad = charValue >= 0; // $ Alert
good = charValue < 255;
good = charValue > 0;
bad = byteValue >= byte.MinValue;
bad = byteValue <= byte.MaxValue;
bad = byteValue >= byte.MinValue; // $ Alert
bad = byteValue <= byte.MaxValue; // $ Alert
good = byteValue > byte.MinValue;
good = byteValue < byte.MaxValue;
bad = sbyteValue >= sbyte.MinValue;
bad = sbyteValue <= sbyte.MaxValue;
bad = sbyteValue >= sbyte.MinValue; // $ Alert
bad = sbyteValue <= sbyte.MaxValue; // $ Alert
good = sbyteValue < sbyte.MaxValue;
good = sbyteValue > sbyte.MinValue;
bad = shortValue >= short.MinValue;
bad = shortValue <= short.MaxValue;
bad = shortValue >= short.MinValue; // $ Alert
bad = shortValue <= short.MaxValue; // $ Alert
good = shortValue > short.MinValue;
good = shortValue < short.MaxValue;
bad = ushortValue >= ushort.MinValue;
bad = ushortValue <= ushort.MaxValue;
bad = ushortValue >= ushort.MinValue; // $ Alert
bad = ushortValue <= ushort.MaxValue; // $ Alert
good = ushortValue > ushort.MinValue;
good = ushortValue < ushort.MaxValue;
bad = intValue >= int.MinValue;
bad = intValue <= int.MaxValue;
bad = intValue >= int.MinValue; // $ Alert
bad = intValue <= int.MaxValue; // $ Alert
good = intValue > int.MinValue;
good = intValue < int.MaxValue;
bad = uintValue >= uint.MinValue;
bad = uintValue >= uint.MinValue; // $ Alert
good = uintValue > uint.MinValue;
bad = ulongValue >= ulong.MinValue;
bad = ulongValue >= ulong.MinValue; // $ Alert
good = ulongValue > ulong.MinValue;
// Explicit casts can cause large values to be truncated or
// to wrap into negative values.
good = (sbyte)byteValue >= 0;
good = (sbyte)byteValue == -1;
bad = (sbyte)byteValue > 127;
bad = (sbyte)byteValue > (sbyte)127;
bad = (sbyte)byteValue > 127; // $ Alert
bad = (sbyte)byteValue > (sbyte)127; // $ Alert
good = (int)uintValue == -1;
good = (sbyte)uintValue == -1;
bad = (sbyte)uintValue == 256;
bad = (sbyte)uintValue == 256; // $ Alert
System.Diagnostics.Debug.Assert(ulongValue >= ulong.MinValue); // GOOD
}

10
csharp/ql/test/query-tests/Bad Practices/Control-Flow/ConstantCondition/ConstantCondition.cs
View File

@@ -59,9 +59,9 @@ class ConstantMatching
{
switch (1 + 2)
{
case 2: // $ Alert
case 2: // Intentionally missing Alert
break;
case 3: // $ Alert
case 3: // Intentionally missing Alert
break;
case int _: // GOOD
break;
@@ -72,7 +72,7 @@ class ConstantMatching
{
switch ((object)s)
{
case int _: // $ Alert
case int _: // Intentionally missing Alert
break;
case "": // GOOD
break;
@@ -92,7 +92,7 @@ class ConstantMatching
{
return o switch
{
_ => o.ToString() // $ Alert
_ => o.ToString() // GOOD, catch-all pattern is fine
};
}
@@ -138,7 +138,7 @@ class ConstantMatching
{
switch (i)
{
case var _: // $ Alert
case var _: // GOOD, catch-all pattern is fine
return "even";
}
}

42
csharp/ql/test/query-tests/Bad Practices/Control-Flow/ConstantCondition/ConstantCondition.expected
View File

@@ -1,31 +1,47 @@
| ConstantComparison.cs:19:15:19:27 | ... < ... | Condition always evaluates to 'false'. | ConstantComparison.cs:19:15:19:27 | ... < ... | dummy |
| ConstantComparison.cs:20:15:20:27 | ... > ... | Condition always evaluates to 'false'. | ConstantComparison.cs:20:15:20:27 | ... > ... | dummy |
| ConstantComparison.cs:21:15:21:28 | ... <= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:21:15:21:28 | ... <= ... | dummy |
| ConstantComparison.cs:22:15:22:28 | ... >= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:22:15:22:28 | ... >= ... | dummy |
| ConstantComparison.cs:24:15:24:29 | ... == ... | Condition always evaluates to 'false'. | ConstantComparison.cs:24:15:24:29 | ... == ... | dummy |
| ConstantComparison.cs:25:15:25:29 | ... != ... | Condition always evaluates to 'true'. | ConstantComparison.cs:25:15:25:29 | ... != ... | dummy |
| ConstantComparison.cs:26:15:26:30 | ... == ... | Condition always evaluates to 'false'. | ConstantComparison.cs:26:15:26:30 | ... == ... | dummy |
| ConstantComparison.cs:27:15:27:30 | ... != ... | Condition always evaluates to 'true'. | ConstantComparison.cs:27:15:27:30 | ... != ... | dummy |
| ConstantComparison.cs:28:15:28:20 | ... != ... | Condition always evaluates to 'true'. | ConstantComparison.cs:28:15:28:20 | ... != ... | dummy |
| ConstantComparison.cs:42:15:42:32 | ... <= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:42:15:42:32 | ... <= ... | dummy |
| ConstantComparison.cs:43:15:43:28 | ... >= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:43:15:43:28 | ... >= ... | dummy |
| ConstantComparison.cs:48:15:48:40 | ... >= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:48:15:48:40 | ... >= ... | dummy |
| ConstantComparison.cs:49:15:49:40 | ... <= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:49:15:49:40 | ... <= ... | dummy |
| ConstantComparison.cs:54:15:54:42 | ... >= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:54:15:54:42 | ... >= ... | dummy |
| ConstantComparison.cs:55:15:55:42 | ... <= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:55:15:55:42 | ... <= ... | dummy |
| ConstantComparison.cs:60:15:60:42 | ... >= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:60:15:60:42 | ... >= ... | dummy |
| ConstantComparison.cs:61:15:61:42 | ... <= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:61:15:61:42 | ... <= ... | dummy |
| ConstantComparison.cs:66:15:66:44 | ... >= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:66:15:66:44 | ... >= ... | dummy |
| ConstantComparison.cs:67:15:67:44 | ... <= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:67:15:67:44 | ... <= ... | dummy |
| ConstantComparison.cs:72:15:72:38 | ... >= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:72:15:72:38 | ... >= ... | dummy |
| ConstantComparison.cs:73:15:73:38 | ... <= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:73:15:73:38 | ... <= ... | dummy |
| ConstantComparison.cs:78:15:78:40 | ... >= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:78:15:78:40 | ... >= ... | dummy |
| ConstantComparison.cs:81:15:81:42 | ... >= ... | Condition always evaluates to 'true'. | ConstantComparison.cs:81:15:81:42 | ... >= ... | dummy |
| ConstantComparison.cs:88:15:88:36 | ... > ... | Condition always evaluates to 'false'. | ConstantComparison.cs:88:15:88:36 | ... > ... | dummy |
| ConstantComparison.cs:89:15:89:43 | ... > ... | Condition always evaluates to 'false'. | ConstantComparison.cs:89:15:89:43 | ... > ... | dummy |
| ConstantComparison.cs:92:15:92:37 | ... == ... | Condition always evaluates to 'false'. | ConstantComparison.cs:92:15:92:37 | ... == ... | dummy |
| ConstantCondition.cs:38:18:38:29 | (...) ... | Expression is always 'null'. | ConstantCondition.cs:38:18:38:29 | (...) ... | dummy |
| ConstantCondition.cs:39:18:39:24 | (...) ... | Expression is never 'null'. | ConstantCondition.cs:39:18:39:24 | (...) ... | dummy |
| ConstantCondition.cs:46:17:46:26 | (...) ... | Expression is always 'null'. | ConstantCondition.cs:46:17:46:26 | (...) ... | dummy |
| ConstantCondition.cs:47:17:47:18 | "" | Expression is never 'null'. | ConstantCondition.cs:47:17:47:18 | "" | dummy |
| ConstantCondition.cs:48:13:48:19 | (...) ... | Expression is never 'null'. | ConstantCondition.cs:48:13:48:19 | (...) ... | dummy |
| ConstantCondition.cs:49:13:49:14 | "" | Expression is never 'null'. | ConstantCondition.cs:49:13:49:14 | "" | dummy |
| ConstantCondition.cs:62:18:62:18 | 2 | Pattern never matches. | ConstantCondition.cs:62:18:62:18 | 2 | dummy |
| ConstantCondition.cs:64:18:64:18 | 3 | Pattern always matches. | ConstantCondition.cs:64:18:64:18 | 3 | dummy |
| ConstantCondition.cs:75:18:75:20 | access to type Int32 | Pattern never matches. | ConstantCondition.cs:75:18:75:20 | access to type Int32 | dummy |
| ConstantCondition.cs:95:13:95:13 | _ | Pattern always matches. | ConstantCondition.cs:95:13:95:13 | _ | dummy |
| ConstantCondition.cs:114:13:114:14 | access to parameter b1 | Condition is always true because of $@. | ConstantCondition.cs:110:14:110:15 | access to parameter b1 | access to parameter b1 |
| ConstantCondition.cs:114:19:114:20 | access to parameter b2 | Condition is always true because of $@. | ConstantCondition.cs:112:14:112:15 | access to parameter b2 | access to parameter b2 |
| ConstantCondition.cs:141:22:141:22 | _ | Pattern always matches. | ConstantCondition.cs:141:22:141:22 | _ | dummy |
| ConstantConditionBad.cs:5:16:5:20 | ... > ... | Condition always evaluates to 'false'. | ConstantConditionBad.cs:5:16:5:20 | ... > ... | dummy |
| ConstantConditionalExpressionCondition.cs:11:22:11:34 | ... == ... | Condition always evaluates to 'true'. | ConstantConditionalExpressionCondition.cs:11:22:11:34 | ... == ... | dummy |
| ConstantConditionalExpressionCondition.cs:12:21:12:25 | false | Condition always evaluates to 'false'. | ConstantConditionalExpressionCondition.cs:12:21:12:25 | false | dummy |
| ConstantConditionalExpressionCondition.cs:13:21:13:30 | ... == ... | Condition always evaluates to 'true'. | ConstantConditionalExpressionCondition.cs:13:21:13:30 | ... == ... | dummy |
| ConstantForCondition.cs:9:29:9:33 | false | Condition always evaluates to 'false'. | ConstantForCondition.cs:9:29:9:33 | false | dummy |
| ConstantDoCondition.cs:15:22:15:34 | ... == ... | Condition always evaluates to 'true'. | ConstantDoCondition.cs:15:22:15:34 | ... == ... | dummy |
| ConstantDoCondition.cs:32:22:32:31 | ... == ... | Condition always evaluates to 'true'. | ConstantDoCondition.cs:32:22:32:31 | ... == ... | dummy |
| ConstantForCondition.cs:11:29:11:34 | ... == ... | Condition always evaluates to 'false'. | ConstantForCondition.cs:11:29:11:34 | ... == ... | dummy |
| ConstantIfCondition.cs:11:17:11:29 | ... == ... | Condition always evaluates to 'true'. | ConstantIfCondition.cs:11:17:11:29 | ... == ... | dummy |
| ConstantIfCondition.cs:14:17:14:21 | false | Condition always evaluates to 'false'. | ConstantIfCondition.cs:14:17:14:21 | false | dummy |
| ConstantIfCondition.cs:17:17:17:26 | ... == ... | Condition always evaluates to 'true'. | ConstantIfCondition.cs:17:17:17:26 | ... == ... | dummy |
| ConstantIsNullOrEmpty.cs:10:21:10:54 | call to method IsNullOrEmpty | Condition always evaluates to 'false'. | ConstantIsNullOrEmpty.cs:10:21:10:54 | call to method IsNullOrEmpty | dummy |
| ConstantIsNullOrEmpty.cs:46:21:46:46 | call to method IsNullOrEmpty | Condition always evaluates to 'true'. | ConstantIsNullOrEmpty.cs:46:21:46:46 | call to method IsNullOrEmpty | dummy |
| ConstantIsNullOrEmpty.cs:50:21:50:44 | call to method IsNullOrEmpty | Condition always evaluates to 'true'. | ConstantIsNullOrEmpty.cs:50:21:50:44 | call to method IsNullOrEmpty | dummy |
| ConstantIsNullOrEmpty.cs:54:21:54:45 | call to method IsNullOrEmpty | Condition always evaluates to 'false'. | ConstantIsNullOrEmpty.cs:54:21:54:45 | call to method IsNullOrEmpty | dummy |
| ConstantIfCondition.cs:35:20:35:25 | ... >= ... | Condition always evaluates to 'true'. | ConstantIfCondition.cs:35:20:35:25 | ... >= ... | dummy |
| ConstantNullCoalescingLeftHandOperand.cs:11:24:11:34 | access to constant NULL_OBJECT | Expression is never 'null'. | ConstantNullCoalescingLeftHandOperand.cs:11:24:11:34 | access to constant NULL_OBJECT | dummy |
| ConstantNullCoalescingLeftHandOperand.cs:12:24:12:27 | null | Expression is always 'null'. | ConstantNullCoalescingLeftHandOperand.cs:12:24:12:27 | null | dummy |
| ConstantWhileCondition.cs:12:20:12:32 | ... == ... | Condition always evaluates to 'true'. | ConstantWhileCondition.cs:12:20:12:32 | ... == ... | dummy |
| ConstantWhileCondition.cs:16:20:16:24 | false | Condition always evaluates to 'false'. | ConstantWhileCondition.cs:16:20:16:24 | false | dummy |
| ConstantWhileCondition.cs:24:20:24:29 | ... == ... | Condition always evaluates to 'true'. | ConstantWhileCondition.cs:24:20:24:29 | ... == ... | dummy |

2
csharp/ql/test/query-tests/Bad Practices/Control-Flow/ConstantCondition/ConstantConditionalExpressionCondition.cs
View File

@@ -9,7 +9,7 @@ namespace ConstantConditionalExpression
public void Foo()
{
int i = (ZERO == 1 - 1) ? 0 : 1; // $ Alert
int j = false ? 0 : 1; // $ Alert
int j = false ? 0 : 1; // GOOD, literal false is likely intentional
int k = " " == " " ? 0 : 1; // $ Alert
int l = (" "[0] == ' ') ? 0 : 1; // Missing Alert
int m = Bar() == 0 ? 0 : 1; // GOOD

4
csharp/ql/test/query-tests/Bad Practices/Control-Flow/ConstantCondition/ConstantDoCondition.cs
View File

@@ -12,7 +12,7 @@ namespace ConstantDoCondition
do
{
break;
} while (ZERO == 1 - 1); // BAD
} while (ZERO == 1 - 1); // $ Alert
do
{
break;
@@ -29,7 +29,7 @@ namespace ConstantDoCondition
do
{
break;
} while (" " == " "); // BAD
} while (" " == " "); // $ Alert
do
{
break;

2
csharp/ql/test/query-tests/Bad Practices/Control-Flow/ConstantCondition/ConstantForCondition.cs
View File

@@ -6,7 +6,7 @@ namespace ConstantForCondition
{
public void M()
{
for (int i = 0; false; i++) // $ Alert
for (int i = 0; false; i++) // GOOD, literal false is likely intentional
;
for (int i = 0; 0 == 1; i++) // $ Alert
;

7
csharp/ql/test/query-tests/Bad Practices/Control-Flow/ConstantCondition/ConstantIfCondition.cs
View File

@@ -11,7 +11,7 @@ namespace ConstantIfCondition
if (ZERO == 1 - 1) // $ Alert
{
}
if (false) // $ Alert
if (false) // GOOD
{
}
if (" " == " ") // $ Alert
@@ -30,6 +30,11 @@ namespace ConstantIfCondition
return ZERO;
}
public void UnsignedCheck(byte n)
{
while (n >= 0) { n--; } // $ Alert
}
}
}

11
csharp/ql/test/query-tests/Bad Practices/Control-Flow/ConstantCondition/ConstantIsNullOrEmpty.cs
View File

@@ -7,7 +7,10 @@ namespace ConstantIsNullOrEmpty
static void Main(string[] args)
{
{
if (string.IsNullOrEmpty(nameof(args))) // $ Alert
// All of the IsNullOrEmpty constant checks have been descoped
// from the query as it didn't seem worth the effort to keep them.
if (string.IsNullOrEmpty(nameof(args))) // Missing Alert (always false)
{
}
@@ -43,15 +46,15 @@ namespace ConstantIsNullOrEmpty
{
}
if (string.IsNullOrEmpty(null)) // $ Alert
if (string.IsNullOrEmpty(null)) // Missing Alert
{
}
if (string.IsNullOrEmpty("")) // $ Alert
if (string.IsNullOrEmpty("")) // Missing Alert
{
}
if (string.IsNullOrEmpty(" ")) // $ Alert
if (string.IsNullOrEmpty(" ")) // Missing Alert
{
}
}

2
csharp/ql/test/query-tests/Bad Practices/Control-Flow/ConstantCondition/ConstantWhileCondition.cs
View File

@@ -13,7 +13,7 @@ namespace ConstantWhileCondition
{
break;
}
while (false) // $ Alert
while (false) // Silly, but likely intentional
{
break;
}

26
csharp/ql/test/query-tests/Likely Bugs/ConstantComparison/ConstantComparison.expected
View File

@@ -1,26 +0,0 @@
| ConstantComparison.cs:19:15:19:27 | ... < ... | This comparison is always false. |
| ConstantComparison.cs:20:15:20:27 | ... > ... | This comparison is always false. |
| ConstantComparison.cs:21:15:21:28 | ... <= ... | This comparison is always true. |
| ConstantComparison.cs:22:15:22:28 | ... >= ... | This comparison is always true. |
| ConstantComparison.cs:24:15:24:29 | ... == ... | This comparison is always false. |
| ConstantComparison.cs:25:15:25:29 | ... != ... | This comparison is always true. |
| ConstantComparison.cs:26:15:26:30 | ... == ... | This comparison is always false. |
| ConstantComparison.cs:27:15:27:30 | ... != ... | This comparison is always true. |
| ConstantComparison.cs:28:15:28:20 | ... != ... | This comparison is always true. |
| ConstantComparison.cs:42:15:42:32 | ... <= ... | This comparison is always true. |
| ConstantComparison.cs:43:15:43:28 | ... >= ... | This comparison is always true. |
| ConstantComparison.cs:48:15:48:40 | ... >= ... | This comparison is always true. |
| ConstantComparison.cs:49:15:49:40 | ... <= ... | This comparison is always true. |
| ConstantComparison.cs:54:15:54:42 | ... >= ... | This comparison is always true. |
| ConstantComparison.cs:55:15:55:42 | ... <= ... | This comparison is always true. |
| ConstantComparison.cs:60:15:60:42 | ... >= ... | This comparison is always true. |
| ConstantComparison.cs:61:15:61:42 | ... <= ... | This comparison is always true. |
| ConstantComparison.cs:66:15:66:44 | ... >= ... | This comparison is always true. |
| ConstantComparison.cs:67:15:67:44 | ... <= ... | This comparison is always true. |
| ConstantComparison.cs:72:15:72:38 | ... >= ... | This comparison is always true. |
| ConstantComparison.cs:73:15:73:38 | ... <= ... | This comparison is always true. |
| ConstantComparison.cs:78:15:78:40 | ... >= ... | This comparison is always true. |
| ConstantComparison.cs:81:15:81:42 | ... >= ... | This comparison is always true. |
| ConstantComparison.cs:88:15:88:36 | ... > ... | This comparison is always false. |
| ConstantComparison.cs:89:15:89:43 | ... > ... | This comparison is always false. |
| ConstantComparison.cs:92:15:92:37 | ... == ... | This comparison is always false. |

1
csharp/ql/test/query-tests/Likely Bugs/ConstantComparison/ConstantComparison.qlref
View File

@@ -1 +0,0 @@
Likely Bugs/ConstantComparison.ql

2
csharp/ql/test/query-tests/Likely Bugs/ConstantComparison/options
View File

@@ -1,2 +0,0 @@
semmle-extractor-options: /nostdlib /noconfig
semmle-extractor-options: --load-sources-from-project:${testdir}/../../../resources/stubs/_frameworks/Microsoft.NETCore.App/Microsoft.NETCore.App.csproj

2
csharp/ql/test/query-tests/standalone/Bad Practices/Control-Flow/ConstantCondition/ConstantCondition.cs
View File

@@ -12,7 +12,7 @@ class ConstantMatching
void M1()
{
var c1 = new C1();
if (c1.Prop is int) // $ Alert
if (c1.Prop is int) // Descoped, no longer reported by the query.
{
}

2
csharp/ql/test/query-tests/standalone/Bad Practices/Control-Flow/ConstantCondition/ConstantCondition.expected
View File

@@ -1,2 +0,0 @@
| ConstantCondition.cs:15:13:15:26 | ... is ... | Condition always evaluates to 'false'. | ConstantCondition.cs:15:13:15:26 | ... is ... | dummy |
| ConstantCondition.cs:15:24:15:26 | access to type Int32 | Pattern never matches. | ConstantCondition.cs:15:24:15:26 | access to type Int32 | dummy |