hohn/codeql
1
0
Fork 0
mirror of https://github.com/github/codeql.git synced 2025-12-21 19:26:31 +01:00
Code Issues Packages Projects Releases Wiki Activity

C++: Exclude all parenthesized CommaExprs.

Browse Source
This commit is contained in:
Nora Dimitrijević
2022-09-29 15:49:29 +02:00
parent 909b36a078
commit 64903336f7
2 changed files with 31 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
cpp/ql/src/Best Practices/Likely Errors/CommaBeforeMisleadingIndentation.ql
View File

@@ -36,6 +36,14 @@ predicate isInDecltypeOrSizeof(CommaExpr ce) {
ce.getParent*() = any(Decltype d).getExpr()
}
predicate isParenthesized(CommaExpr ce) {
isInLoopHead(ce)
or
isInDecltypeOrSizeof(ce)
or
ce.getParent*().(Expr).isParenthesised()
}
from CommaExpr ce, Expr left, Expr right, Location leftLoc, Location rightLoc
where
ce.fromSource() and
@@ -44,8 +52,7 @@ where
right = normalizeExpr(ce.getRightOperand()) and
leftLoc = left.getLocation() and
rightLoc = right.getLocation() and
not isInLoopHead(ce) and // <- HACK to reduce FPs in loop heads; assumption: unlikely to be misread due to '(', ')' delimiters
not isInDecltypeOrSizeof(ce) and // <- Removes arguable FPs since, like function calls (and loop heads), these Exprs have clear delimiters.
not isParenthesized(ce) and
leftLoc.getEndLine() < rightLoc.getStartLine() and
leftLoc.getStartColumn() > rightLoc.getStartColumn()
select right, "The indentation level may be misleading (for some tab sizes)."

33
cpp/ql/test/query-tests/Best Practices/Likely Errors/CommaBeforeMisleadingIndentation/test.cpp
View File

@@ -44,6 +44,9 @@ int Foo::test(int (*baz)(int))
(void)i, // BAD
(void)j;
if (1) FOO(i),
(void)x.foo(j); // BAD
// Parenthesized comma (borderline example):
foo(i++), j++; // GOOD
@@ -51,28 +54,36 @@ int Foo::test(int (*baz)(int))
(foo(i++), // GOOD
j++);
(foo(i++),
j++); // BAD (?)
foo(i++),
j++, // GOOD (?) -- Currently explicitly excluded
j++);
x.foo(i++), j++; // GOOD
(x.foo(i++), j++); // GOOD
(x.foo(i++), // GOOD
j++);
(x.foo(i++),
j++); // BAD (?)
x.foo(i++),
j++, // GOOD (?) -- Currently explicitly excluded
j++);
FOO(i++), j++; // GOOD
(FOO(i++), j++); // GOOD
(FOO(i++), // GOOD
j++);
(FOO(i++),
j++); // BAD (?)
FOO(i++),
j++, // GOOD (?) -- Currently explicitly excluded
j++);
(void)(i++), j++; // GOOD
((void)(i++), j++); // GOOD
((void)(i++), // GOOD
j++);
((void)(i++),
j++); // BAD (?)
(void)(i++),
j++, // GOOD (?) -- Currently explicitly excluded
j++);
// Comma in argument list doesn't count:
@@ -102,7 +113,7 @@ int Foo::test(int (*baz)(int))
j++);
BAZ("%d %d\n", i,
j); // GOOD [FALSE POSITIVE] -- but can only be excluded by excluding all parenthesized commas (which sounds like a good idea actually)
j); // GOOD -- Currently explicitly excluded
// Comma in loops
@@ -128,10 +139,10 @@ int Foo::test(int (*baz)(int))
// Mixed tabs and spaces (ugly case):
for (i = 0, // GOOD if tab >= 4 spaces else BAD -- can't exclude w/o source code text :/
for (i = 0, // GOOD if tab >= 4 spaces else BAD -- Currently ignoring loop heads.
j = 0;
i + j < 10;
i++, // GOOD if tab >= 4 spaces else BAD -- can't exclude w/o source code text :/
i++, // GOOD if tab >= 4 spaces else BAD -- Currently ignoring loop heads.
j++);
if (i)
@@ -140,13 +151,13 @@ int Foo::test(int (*baz)(int))
// LHS ends on same line RHS begins on:
int k1 = (foo(
if (1) foo(
i++
), j++); // GOOD? [FALSE POSITIVE]
), j++; // GOOD? [FALSE POSITIVE]
int k2 = (baz(
if (1) baz(
i++
), j++); // GOOD when it's a function-pointer call!?
), j++; // GOOD... when calling a function pointer..!?
// Weird cases: