| """Internal functions to parse versions.""" |
| |
| def _safe_int(s, v): |
| if not s.isdigit(): |
| fail("invalid Bazel version '{}': non-numeric segment '{}'".format(v, s)) |
| return int(s) |
| |
| def _partition(s): |
| for i in range(len(s)): |
| c = s[i] |
| if c == "-": |
| return s[:i], s[i + 1:] |
| if not c.isdigit() and c != ".": |
| return s[:i], s[i:] |
| return s, "" |
| |
| def _parse_prerelease(prerelease): |
| # Parses a SemVer prerelease string into a list of comparable identifiers, following the |
| # precedence rules at https://semver.org/#spec-item-11. |
| if not prerelease: |
| return [] |
| identifiers = [] |
| for ident in prerelease.split("."): |
| if ident.isdigit(): |
| identifiers.append((0, int(ident))) |
| else: |
| identifiers.append((1, ident)) |
| return identifiers |
| |
| def parse_version(v): |
| """Parses the given Bazel version string into a comparable value. |
| |
| Args: |
| v (str): version string |
| |
| Returns: |
| a triple ([major, minor, patch], is_released, prerelease) |
| """ |
| if not v: |
| # An empty string is treated as a "dev version", which is greater than anything. |
| v = "999999.999999.999999" |
| release, prerelease = _partition(v.partition(" ")[0]) |
| segments = release.split(".") |
| if len(segments) != 3: |
| fail("invalid Bazel version '{}': got {} dot-separated segments, want 3".format(v, len(segments))) |
| if prerelease.startswith("rc") and len(prerelease) > 2 and prerelease[2:].isdigit(): |
| # Release candidates are considered to be the same as the release version for the purpose of |
| # feature detection. This allows for realistic testing of candidates and avoids the need to |
| # specify "rc1" on every version. |
| prerelease = "" |
| return [_safe_int(s, v) for s in segments], not prerelease, _parse_prerelease(prerelease) |
