chainlint.pl: add parser to validate tests
Continue fleshing out chainlint.pl by adding TestParser, a parser with special knowledge about how Git tests should be written; for instance, it knows that commands within a test body should be chained together with `&&`. An upcoming parser which plucks test definitions from test scripts will invoke TestParser for each test body it encounters. Signed-off-by: Eric Sunshine <sunshine@sunshineco.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Eric Sunshine committed
Sep 1, 2022 at 00:29 UTC
6d932e92fcb49b59b780bc018fe550d867bb3d84
1 file changed
+46
t/chainlint.pl
+46
@@ -441,6 +441,52 @@ DONE:
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return @tokens;
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}
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+# TestParser is a subclass of ShellParser which, beyond parsing shell script
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+# code, is also imbued with semantic knowledge of test construction, and checks
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+# tests for common problems (such as broken &&-chains) which might hide bugs in
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+# the tests themselves or in behaviors being exercised by the tests. As such,
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+# TestParser is only called upon to parse test bodies, not the top-level
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+# scripts in which the tests are defined.
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+package TestParser;
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+
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+use base 'ShellParser';
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+
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+sub find_non_nl {
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+ my $tokens = shift @_;
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+ my $n = shift @_;
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+ $n = $#$tokens if !defined($n);
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+ $n-- while $n >= 0 && $$tokens[$n] eq "\n";
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+ return $n;
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+}
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+
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+sub ends_with {
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+ my ($tokens, $needles) = @_;
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+ my $n = find_non_nl($tokens);
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+ for my $needle (reverse(@$needles)) {
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+ return undef if $n < 0;
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+ $n = find_non_nl($tokens, $n), next if $needle eq "\n";
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+ return undef if $$tokens[$n] !~ $needle;
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+ $n--;
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+ }
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+ return 1;
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+}
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+
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+sub accumulate {
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+ my ($self, $tokens, $cmd) = @_;
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+ goto DONE unless @$tokens;
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+ goto DONE if @$cmd == 1 && $$cmd[0] eq "\n";
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+
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+ # did previous command end with "&&", "||", "|"?
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+ goto DONE if ends_with($tokens, [qr/^(?:&&|\|\||\|)$/]);
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+
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+ # flag missing "&&" at end of previous command
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+ my $n = find_non_nl($tokens);
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+ splice(@$tokens, $n + 1, 0, '?!AMP?!') unless $n < 0;
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+
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+DONE:
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+ $self->SUPER::accumulate($tokens, $cmd);
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+}
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+
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package ScriptParser;
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sub new {