Now that chainlint.pl is functional, take advantage of the existing
chainlint self-tests to validate its operation. (While at it, stop
validating chainlint.sed against the self-tests since it will soon be
retired.)
Due to chainlint.sed implementation limitations leaking into the
self-test "expect" files, a few of them require minor adjustment to make
them compatible with chainlint.pl which does not share those
limitations.
First, because `sed` does not provide any sort of real recursion,
chainlint.sed only emulates recursion into subshells, and each level of
recursion leads to a multiplicative increase in complexity of the `sed`
rules. To avoid substantial complexity, chainlint.sed, therefore, only
emulates subshell recursion one level deep. Any subshell deeper than
that is passed through as-is, which means that &&-chains are not checked
in deeper subshells. chainlint.pl, on the other hand, employs a proper
recursive descent parser, thus checks subshells to any depth and
correctly flags broken &&-chains in deep subshells.
Second, due to sed's line-oriented nature, chainlint.sed, by necessity,
folds multi-line quoted strings into a single line. chainlint.pl, on the
other hand, employs a proper lexical analyzer which preserves quoted
strings as-is, including embedded newlines.
Furthermore, the output of chainlint.sed and chainlint.pl do not match
precisely in terms of whitespace. However, since the purpose of the
self-checks is to verify that the ?!AMP?! annotations are being
correctly added, minor whitespace differences are immaterial. For this
reason, rather than adjusting whitespace in all existing self-test
"expect" files to match the new linter's output, the `check-chainlint`
target ignores whitespace differences. Since `diff -w` is not POSIX,
`check-chainlint` attempts to employ `git diff -w`, and only falls back
to non-POSIX `diff -w` (and `-u`) if `git diff` is not available.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The purpose of chainlint is to highlight problems it finds in test code
by inserting annotations at the location of each problem. Arbitrarily
eliding bits of the code it is checking is not helpful, yet this is
exactly what chainlint.sed does by cavalierly and unnecessarily dropping
the here-doc operator and tag; i.e. `cat <<TAG` becomes simply `cat` in
the output. This behavior can make it more difficult for the test writer
to align the annotated output of chainlint.sed with the original test
code. Address this by retaining here-doc tags.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
chainlint.sed inserts a ">" annotation at the beginning of a line to
signal that its heuristics have identified an end-of-subshell. This was
useful as a debugging aid during development of the script, but it has
no value to test writers and might even confuse them into thinking that
the linter is misbehaving by inserting line-noise into the shell code it
is validating. Moreover, its presence also potentially makes it
difficult to reuse the chainlint self-test "expect" output should a more
capable linter ever be developed. Therefore, drop the ">" annotation.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The chainlint self-test code snippets are supposed to represent the body
of a test_expect_success() or test_expect_failure(), yet the contents of
a few tests would have caused the shell to report syntax errors had they
been real test bodies due to the mix of single- and double-quotes.
Although chainlint.sed, with its simplistic heuristics, is blind to this
problem, a future more robust chainlint implementation might not have
such a limitation. Therefore, stop mixing quote types haphazardly in
those tests and unify quoting throughout. While at it, drop chunks of
tests which merely repeat what is already tested elsewhere but with
alternative quotes.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This extract from contrib/subtree/t7900 triggered a false positive due
to three chainlint limitations:
* recognizing only a "blessed" set of here-doc tag names in a subshell
("EOF", "EOT", "INPUT_END"), of which "TXT" is not a member
* inability to recognize multi-line $(...) when the first statement of
the body is cuddled with the opening "$("
* inability to recognize multiple constructs on a single line, such as
opening a multi-line $(...) and starting a here-doc
Now that all of these shortcomings have been addressed, turn this rather
pathological bit of shell coding into a chainlint test case.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Eric Sunshine