Crate uv_requirements_txt 

Parses a subset of requirement.txt syntax

https://pip.pypa.io/en/stable/reference/requirements-file-format/

Supported:

• PEP 508 requirements
• -r
• -c
• --hash (postfix)
• -e

Unsupported:

• <path>. TBD
• <archive_url>. TBD
• Options without a requirement, such as --find-links or --index-url

Grammar as implemented:

file = (statement | empty ('#' any*)? '\n')*
empty = whitespace*
statement = constraint_include | requirements_include | editable_requirement | requirement
constraint_include = '-c' ('=' | wrappable_whitespaces) filepath
requirements_include = '-r' ('=' | wrappable_whitespaces) filepath
editable_requirement = '-e' ('=' | wrappable_whitespaces) requirement
# We check whether the line starts with a letter or a number, in that case we assume it's a
# PEP 508 requirement
# https://packaging.python.org/en/latest/specifications/name-normalization/#valid-non-normalized-names
# This does not (yet?) support plain files or urls, we use a letter or a number as first
# character to assume a PEP 508 requirement
requirement = [a-zA-Z0-9] pep508_grammar_tail wrappable_whitespaces hashes
hashes = ('--hash' ('=' | wrappable_whitespaces) [a-zA-Z0-9-_]+ ':' [a-zA-Z0-9-_] wrappable_whitespaces+)*
# This should indicate a single backslash before a newline
wrappable_whitespaces = whitespace ('\\\n' | whitespace)*

Structs

RequirementEntry

A Requirement with additional metadata from the requirements.txt, currently only hashes but in the future also editable and similar information.

RequirementsTxt

Parsed and flattened requirements.txt with requirements and constraints

RequirementsTxtFileError

Error parsing requirements.txt, wrapper with filename

Enums

RequirementsTxtParserError

Error parsing requirements.txt, error disambiguation

RequirementsTxtRequirement

A requirement specifier in a requirements.txt file.

Type Aliases

SourceCache

A cache of file contents, keyed by path, to avoid re-reading files from disk.