fix: version parsing for release candidates (#3593)

the npm spec library is buggy and does not handle release candidates
correctly. switch to the pypa packaging library which does pep440. note
that we do a hack in order to support commonly used npm prefixes: no
prefix, and `^` as prefix. going forward in v0.4.x, we will switch to
pep440 entirely.

docs/structure-of-a-contract.rst

@@ -17,7 +17,7 @@ Vyper supports several source code directives to control compiler modes and help
 Version Pragma
 --------------
 
-The version pragma ensures that a contract is only compiled by the intended compiler version, or range of versions. Version strings use `NPM <https://docs.npmjs.com/about-semantic-versioning>`_ style syntax.
+The version pragma ensures that a contract is only compiled by the intended compiler version, or range of versions. Version strings use `NPM <https://docs.npmjs.com/about-semantic-versioning>`_ style syntax. Starting from v0.4.0 and up, version strings will use `PEP440 version specifiers <https://peps.python.org/pep-0440/#version-specifiers>_`.
 
 As of 0.3.10, the recommended way to specify the version pragma is as follows:
 

tests/ast/test_pre_parser.py

@@ -21,16 +21,9 @@ def set_version(version):
     "0.1.1",
     ">0.0.1",
     "^0.1.0",
-    "<=1.0.0 >=0.1.0",
-    "0.1.0 - 1.0.0",
-    "~0.1.0",
-    "0.1",
-    "0",
-    "*",
-    "x",
-    "0.x",
-    "0.1.x",
-    "0.2.0 || 0.1.1",
+    "<=1.0.0,>=0.1.0",
+    # "0.1.0 - 1.0.0",
+    "~=0.1.0",
 ]
 invalid_versions = [
     "0.1.0",
@@ -44,7 +37,6 @@ def set_version(version):
     "1.x",
     "0.2.x",
     "0.2.0 || 0.1.3",
-    "==0.1.1",
     "abc",
 ]
 
@@ -70,29 +62,19 @@ def test_invalid_version_pragma(file_version, mock_version):
     "<0.1.1-rc.1",
     ">0.1.1a1",
     ">0.1.1-alpha.1",
-    "0.1.1a9 - 0.1.1-rc.10",
+    ">=0.1.1a9,<=0.1.1-rc.10",
     "<0.1.1b8",
     "<0.1.1rc1",
+    "<0.2.0",
 ]
 prerelease_invalid_versions = [
     ">0.1.1-beta.9",
     ">0.1.1b9",
     "0.1.1b8",
     "0.1.1rc2",
     "0.1.1-rc.9 - 0.1.1-rc.10",
-    "<0.2.0",
-    pytest.param(
-        "<0.1.1b1",
-        marks=pytest.mark.xfail(
-            reason="https://github.com/rbarrois/python-semanticversion/issues/100"
-        ),
-    ),
-    pytest.param(
-        "<0.1.1a9",
-        marks=pytest.mark.xfail(
-            reason="https://github.com/rbarrois/python-semanticversion/issues/100"
-        ),
-    ),
+    "<0.1.1b1",
+    "<0.1.1a9",
 ]
 
 

vyper/ast/pre_parser.py

@@ -2,7 +2,7 @@
 import re
 from tokenize import COMMENT, NAME, OP, TokenError, TokenInfo, tokenize, untokenize
 
-from semantic_version import NpmSpec, Version
+from packaging.specifiers import InvalidSpecifier, SpecifierSet
 
 from vyper.compiler.settings import OptimizationLevel, Settings
 
@@ -12,50 +12,33 @@
 from vyper.exceptions import StructureException, SyntaxException, VersionException
 from vyper.typing import ModificationOffsets, ParserPosition
 
-VERSION_ALPHA_RE = re.compile(r"(?<=\d)a(?=\d)")  # 0.1.0a17
-VERSION_BETA_RE = re.compile(r"(?<=\d)b(?=\d)")  # 0.1.0b17
-VERSION_RC_RE = re.compile(r"(?<=\d)rc(?=\d)")  # 0.1.0rc17
-
-
-def _convert_version_str(version_str: str) -> str:
-    """
-    Convert loose version (0.1.0b17) to strict version (0.1.0-beta.17)
-    """
-    version_str = re.sub(VERSION_ALPHA_RE, "-alpha.", version_str)  # 0.1.0-alpha.17
-    version_str = re.sub(VERSION_BETA_RE, "-beta.", version_str)  # 0.1.0-beta.17
-    version_str = re.sub(VERSION_RC_RE, "-rc.", version_str)  # 0.1.0-rc.17
-
-    return version_str
-
 
 def validate_version_pragma(version_str: str, start: ParserPosition) -> None:
     """
     Validates a version pragma directive against the current compiler version.
     """
     from vyper import __version__
 
-    # NOTE: should be `x.y.z.*`
-    installed_version = ".".join(__version__.split(".")[:3])
-
-    strict_file_version = _convert_version_str(version_str)
-    strict_compiler_version = Version(_convert_version_str(installed_version))
-
-    if len(strict_file_version) == 0:
+    if len(version_str) == 0:
         raise VersionException("Version specification cannot be empty", start)
 
+    # X.Y.Z or vX.Y.Z => ==X.Y.Z, ==vX.Y.Z
+    if re.match("[v0-9]", version_str):
+        version_str = "==" + version_str
+    # convert npm to pep440
+    version_str = re.sub("^\\^", "~=", version_str)
+
     try:
-        npm_spec = NpmSpec(strict_file_version)
-    except ValueError:
+        spec = SpecifierSet(version_str)
+    except InvalidSpecifier:
         raise VersionException(
-            f'Version specification "{version_str}" is not a valid NPM semantic '
-            f"version specification",
-            start,
+            f'Version specification "{version_str}" is not a valid PEP440 specifier', start
         )
 
-    if not npm_spec.match(strict_compiler_version):
+    if not spec.contains(__version__, prereleases=True):
         raise VersionException(
             f'Version specification "{version_str}" is not compatible '
-            f'with compiler version "{installed_version}"',
+            f'with compiler version "{__version__}"',
             start,
         )