env: fix errors on valid interpolation expressions #307
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
milas
commented
Sep 23, 2022
| func TestInvalid(t *testing.T) { | ||
| invalidTemplates := []string{ | ||
| "${", | ||
| "$}", |
There was a problem hiding this comment.
This is valid and is in the new test cases above.
❯ echo "$}"
$}
|
@milas can you sign-off your commit please 😂 ? |
milas
commented
Sep 23, 2022
| @@ -31,7 +31,7 @@ var substitutionNamed = "[_a-z][_a-z0-9]*" | |||
| var substitutionBraced = "[_a-z][_a-z0-9]*(?::?[-+?](.*}|[^}]*))?" | |||
|
|
|||
| var patternString = fmt.Sprintf( | |||
| "%s(?i:(?P<escaped>%s)|(?P<named>%s)|{(?P<braced>%s)}|(?P<invalid>))", | |||
| "%s(?i:(?P<escaped>%s)|(?P<named>%s)|{(?:(?P<braced>%s)}|(?P<invalid>)))", | |||
There was a problem hiding this comment.
Here's a playground with the expanded regex and various cases: https://regex101.com/r/H5aQT8/1
There was a problem hiding this comment.
The change here is to move the "invalid" named group (doesn't actually capture anything, used as a sentinel) to be part of the "braced" section so we can detect an unmatched brace, so there's an extra (non-capturing) group.
The parser was too strict here and would reject valid constructs
that used an unescaped `$` that was not part of a variable
expression (and not ambiguous).
Now, only errors for unmatched braced expressions (e.g. `${FOO`)
are returned, but other valid cases are ignored and the `$` will
be treated literally, e.g. `a $ string` -> `a $ string`, which is
the same as in POSIX.
Signed-off-by: Milas Bowman <milas.bowman@docker.com>
milas
force-pushed
the
env-parser-strictness
branch
from
74cfbe9 to
85f1221
Compare
nicksieger
approved these changes
Sep 23, 2022
|
Awesome! |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
The parser was too strict here and would reject valid constructs that used an unescaped
$that was not part of a variable expression (and not ambiguous).Now, only errors for unmatched braced expressions (e.g.
${FOO) are returned, but other valid cases are ignored and the$will be treated literally, e.g.a $ string->a $ string, which is the same as in POSIX.