feat: airplane mode (non-exact compiler version match) [APE-1161] (#114)

Co-authored-by: antazoey <admin@antazoey.me>
Co-authored-by: El De-dog-lo <3859395+fubuloubu@users.noreply.github.com>

ape_solidity/compiler.py

@@ -3,7 +3,6 @@
 from pathlib import Path
 from typing import Any, Dict, List, Optional, Set, Tuple, Type, Union, cast
 
-import solcx  # type: ignore
 from ape.api import CompilerAPI, PluginConfig
 from ape.contracts import ContractInstance
 from ape.exceptions import CompilerError, ContractLogicError
@@ -18,6 +17,11 @@
 from requests.exceptions import ConnectionError
 from semantic_version import NpmSpec, Version  # type: ignore
 from solcx import compile_standard  # type: ignore
+from solcx import (  # type: ignore
+    get_installable_solc_versions,
+    get_installed_solc_versions,
+    install_solc,
+)
 from solcx.exceptions import SolcError  # type: ignore
 from solcx.install import get_executable  # type: ignore
 
@@ -84,15 +88,15 @@ def libraries(self) -> Dict[str, Dict[str, AddressType]]:
     def available_versions(self) -> List[Version]:
         # NOTE: Package version should already be included in available versions
         try:
-            return solcx.get_installable_solc_versions()
+            return get_installable_solc_versions()
         except ConnectionError:
             # Compiling offline
             logger.warning("Internet connection required to fetch installable Solidity versions.")
             return []
 
     @property
     def installed_versions(self) -> List[Version]:
-        return solcx.get_installed_solc_versions()
+        return get_installed_solc_versions()
 
     @cached_property
     def _ape_version(self) -> Version:
@@ -557,7 +561,7 @@ def get_version_map(
         if self.config.version is not None:
             specified_version = Version(self.config.version)
             if specified_version not in self.installed_versions:
-                solcx.install_solc(specified_version)
+                install_solc(specified_version)
 
             specified_version_with_commit_hash = get_version_with_commit_hash(specified_version)
             return {specified_version_with_commit_hash: source_paths_to_get}
@@ -570,7 +574,7 @@ def get_version_map(
         # If no Solidity version has been installed previously while fetching the
         # contract version pragma, we must install a compiler, so choose the latest
         if not self.installed_versions and not any(source_by_pragma_spec.values()):
-            solcx.install_solc(max(self.available_versions), show_progress=False)
+            install_solc(max(self.available_versions), show_progress=False)
 
         # Adjust best-versions based on imports.
         files_by_solc_version: Dict[Version, Set[Path]] = {}
@@ -666,8 +670,22 @@ def _get_pragma_spec(self, path: Path) -> Optional[NpmSpec]:
 
         compiler_version = pragma_spec.select(self.available_versions)
         if compiler_version:
-            solcx.install_solc(compiler_version, show_progress=False)
+            install_solc(compiler_version, show_progress=False)
         else:
+            # Attempt to use the best-installed version.
+            for version in self.installed_versions:
+                if not pragma_spec.match(version):
+                    continue
+
+                logger.warning(
+                    "Ape is unable to determine if additional versions are needed "
+                    f"in order to meet spec {pragma_spec}. Resorting to the best matching "
+                    "already-installed version. Alternatively, specify a Solidity "
+                    "compiler version in your ape-config.yaml."
+                )
+                return pragma_spec
+
+            # None of the installed versions match, and we are unable to install.
             raise CompilerError(f"Solidity version specification '{pragma_spec}' could not be met.")
 
         return pragma_spec

setup.py

@@ -7,6 +7,7 @@
         "pytest>=6.0",  # Core testing package
         "pytest-xdist",  # multi-process runner
         "pytest-cov",  # Coverage analyzer plugin
+        "pytest-mock",  # For creating and using mocks
         "hypothesis>=6.2.0,<7.0",  # Strategy-based fuzzer
     ],
     "lint": [

tests/test_compiler.py

@@ -10,6 +10,7 @@
 from ape.exceptions import CompilerError
 from ethpm_types.ast import ASTClassification
 from pkg_resources import get_distribution
+from requests.exceptions import ConnectionError
 from semantic_version import Version  # type: ignore
 
 from ape_solidity import Extension
@@ -49,6 +50,18 @@ def test_compile(project, contract):
     assert contract.source_id == f"{contract.name}.sol"
 
 
+def test_compile_when_offline(project, compiler, mocker):
+    # When offline, getting solc versions raises a requests connection error.
+    # This should trigger the plugin to return an empty list.
+    patch = mocker.patch("ape_solidity.compiler.get_installable_solc_versions")
+    patch.side_effect = ConnectionError
+
+    # Using a non-specific contract - doesn't matter too much which one.
+    source_path = project.contracts_folder / "MultipleDefinitions.sol"
+    result = compiler.compile([source_path])
+    assert len(result) > 0, "Nothing got compiled."
+
+
 def test_compile_multiple_definitions_in_source(project, compiler):
     source_path = project.contracts_folder / "MultipleDefinitions.sol"
     result = compiler.compile([source_path])