cargo: Load Cargo.lock

Cargo.lock is essentially identical to subprojects/*.wrap files. When a
(sub)project has a Cargo.lock file this allows automatic fallback for
its cargo dependencies.

11 files changed, 147 insertions, 24 deletions

diff --git a/docs/markdown/Wrap-dependency-system-manual.md b/docs/markdown/Wrap-dependency-system-manual.md
index 5f0b473..3983d28 100644
--- a/docs/markdown/Wrap-dependency-system-manual.md
+++ b/docs/markdown/Wrap-dependency-system-manual.md
@@ -377,6 +377,10 @@ Some naming conventions need to be respected:
 - The `extra_deps` variable is pre-defined and can be used to add extra dependencies.
   This is typically used as `extra_deps += dependency('foo')`.
 
+Since *1.5.0* Cargo wraps can also be provided with `Cargo.lock` file at the root
+of (sub)project source tree. Meson will automatically load that file and convert
+it into a serie of wraps definitions.
+
 ## Using wrapped projects
 
 Wraps provide a convenient way of obtaining a project into your
diff --git a/docs/markdown/snippets/cargo_lock.md b/docs/markdown/snippets/cargo_lock.md
new file mode 100644
index 0000000..e38c5ed
--- /dev/null
+++ b/docs/markdown/snippets/cargo_lock.md
@@ -0,0 +1,6 @@
+## Added support `Cargo.lock` file
+
+When a (sub)project has a `Cargo.lock` file at its root, it is loaded to provide
+an automatic fallback for dependencies it defines, fetching code from
+https://crates.io or git. This is identical as providing `subprojects/*.wrap`,
+see [cargo wraps](Wrap-dependency-system-manual.md#cargo-wraps) dependency naming convention.
diff --git a/mesonbuild/cargo/__init__.py b/mesonbuild/cargo/__init__.py
index 0007b9d..10cb0be 100644
--- a/mesonbuild/cargo/__init__.py
+++ b/mesonbuild/cargo/__init__.py
@@ -1,5 +1,6 @@
 __all__ = [
-    'interpret'
+    'interpret',
+    'load_wraps',
 ]
 
-from .interpreter import interpret
+from .interpreter import interpret, load_wraps
diff --git a/mesonbuild/cargo/interpreter.py b/mesonbuild/cargo/interpreter.py
index 1d06474..13568cd 100644
--- a/mesonbuild/cargo/interpreter.py
+++ b/mesonbuild/cargo/interpreter.py
@@ -18,12 +18,14 @@ import json
 import os
 import shutil
 import collections
+import urllib.parse
 import typing as T
 
 from . import builder
 from . import version
 from ..mesonlib import MesonException, Popen_safe, OptionKey
-from .. import coredata, options
+from .. import coredata, options, mlog
+from ..wrap.wrap import PackageDefinition
 
 if T.TYPE_CHECKING:
     from types import ModuleType
@@ -731,3 +733,45 @@ def interpret(subp_name: str, subdir: str, env: Environment) -> T.Tuple[mparser.
             ast.extend(_create_lib(cargo, build, crate_type))
 
     return build.block(ast), project_options
+
+
+def load_wraps(source_dir: str, subproject_dir: str) -> T.List[PackageDefinition]:
+    """ Convert Cargo.lock into a list of wraps """
+
+    wraps: T.List[PackageDefinition] = []
+    filename = os.path.join(source_dir, 'Cargo.lock')
+    if os.path.exists(filename):
+        cargolock = T.cast('manifest.CargoLock', load_toml(filename))
+        for package in cargolock['package']:
+            name = package['name']
+            version = package['version']
+            subp_name = _dependency_name(name, _version_to_api(version))
+            source = package.get('source')
+            if source is None:
+                # This is project's package, or one of its workspace members.
+                pass
+            elif source == 'registry+https://github.com/rust-lang/crates.io-index':
+                url = f'https://crates.io/api/v1/crates/{name}/{version}/download'
+                directory = f'{name}-{version}'
+                wraps.append(PackageDefinition.from_values(subp_name, subproject_dir, 'file', {
+                    'directory': directory,
+                    'source_url': url,
+                    'source_filename': f'{directory}.tar.gz',
+                    'source_hash': package['checksum'],
+                    'method': 'cargo',
+                }))
+            elif source.startswith('git+'):
+                parts = urllib.parse.urlparse(source[4:])
+                query = urllib.parse.parse_qs(parts.query)
+                branch = query['branch'][0] if 'branch' in query else ''
+                revision = parts.fragment or branch
+                url = urllib.parse.urlunparse(parts._replace(params='', query='', fragment=''))
+                wraps.append(PackageDefinition.from_values(subp_name, subproject_dir, 'git', {
+                    'directory': name,
+                    'url': url,
+                    'revision': revision,
+                    'method': 'cargo',
+                }))
+            else:
+                mlog.warning(f'Unsupported source URL in {filename}: {source}')
+    return wraps
diff --git a/mesonbuild/cargo/manifest.py b/mesonbuild/cargo/manifest.py
index e6192d0..183d91e 100644
--- a/mesonbuild/cargo/manifest.py
+++ b/mesonbuild/cargo/manifest.py
@@ -225,3 +225,20 @@ class VirtualManifest(TypedDict):
     """
 
     workspace: Workspace
+
+class CargoLockPackage(TypedDict, total=False):
+
+    """A description of a package in the Cargo.lock file format."""
+
+    name: str
+    version: str
+    source: str
+    checksum: str
+
+
+class CargoLock(TypedDict, total=False):
+
+    """A description of the Cargo.lock file format."""
+
+    version: str
+    package: T.List[CargoLockPackage]
diff --git a/mesonbuild/wrap/wrap.py b/mesonbuild/wrap/wrap.py
index 96b0ef3..4e98c60 100644
--- a/mesonbuild/wrap/wrap.py
+++ b/mesonbuild/wrap/wrap.py
@@ -324,25 +324,32 @@ class Resolver:
             mlog.warning(f'failed to process netrc file: {e}.', fatal=False)
 
     def load_wraps(self) -> None:
-        if not os.path.isdir(self.subdir_root):
-            return
-        root, dirs, files = next(os.walk(self.subdir_root))
-        ignore_dirs = {'packagecache', 'packagefiles'}
-        for i in files:
-            if not i.endswith('.wrap'):
-                continue
-            fname = os.path.join(self.subdir_root, i)
-            wrap = PackageDefinition.from_wrap_file(fname, self.subproject)
-            self.wraps[wrap.name] = wrap
-            ignore_dirs |= {wrap.directory, wrap.name}
-        # Add dummy package definition for directories not associated with a wrap file.
-        for i in dirs:
-            if i in ignore_dirs:
-                continue
-            fname = os.path.join(self.subdir_root, i)
-            wrap = PackageDefinition.from_directory(fname)
-            self.wraps[wrap.name] = wrap
-
+        # Load Cargo.lock at the root of source tree
+        source_dir = os.path.dirname(self.subdir_root)
+        if os.path.exists(os.path.join(source_dir, 'Cargo.lock')):
+            from .. import cargo
+            for wrap in cargo.load_wraps(source_dir, self.subdir_root):
+                self.wraps[wrap.name] = wrap
+        # Load subprojects/*.wrap
+        if os.path.isdir(self.subdir_root):
+            root, dirs, files = next(os.walk(self.subdir_root))
+            for i in files:
+                if not i.endswith('.wrap'):
+                    continue
+                fname = os.path.join(self.subdir_root, i)
+                wrap = PackageDefinition.from_wrap_file(fname, self.subproject)
+                self.wraps[wrap.name] = wrap
+            # Add dummy package definition for directories not associated with a wrap file.
+            ignore_dirs = {'packagecache', 'packagefiles'}
+            for wrap in self.wraps.values():
+                ignore_dirs |= {wrap.directory, wrap.name}
+            for i in dirs:
+                if i in ignore_dirs:
+                    continue
+                fname = os.path.join(self.subdir_root, i)
+                wrap = PackageDefinition.from_directory(fname)
+                self.wraps[wrap.name] = wrap
+        # Add provided deps and programs into our lookup tables
         for wrap in self.wraps.values():
             self.add_wrap(wrap)
 
diff --git a/run_unittests.py b/run_unittests.py
index 33b0e09..84edb34 100755
--- a/run_unittests.py
+++ b/run_unittests.py
@@ -25,7 +25,7 @@ from mesonbuild.mesonlib import python_command, setup_vsenv
 import mesonbuild.modules.pkgconfig
 
 from unittests.allplatformstests import AllPlatformTests
-from unittests.cargotests import CargoVersionTest, CargoCfgTest
+from unittests.cargotests import CargoVersionTest, CargoCfgTest, CargoLockTest
 from unittests.darwintests import DarwinTests
 from unittests.failuretests import FailureTests
 from unittests.linuxcrosstests import LinuxCrossArmTests, LinuxCrossMingwTests
diff --git a/test cases/rust/25 cargo lock/Cargo.lock b/test cases/rust/25 cargo lock/Cargo.lock
new file mode 100644
index 0000000..9bc9814
--- /dev/null
+++ b/test cases/rust/25 cargo lock/Cargo.lock
@@ -0,0 +1,7 @@
+version = 3
+
+[[package]]
+name = "bar"
+version = "0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cc2f34e570dcd5f9fe32e6863ee16ee73a356d3b77bce0d8c78501b8bc81a860"
diff --git a/test cases/rust/25 cargo lock/meson.build b/test cases/rust/25 cargo lock/meson.build
new file mode 100644
index 0000000..b359f7b
--- /dev/null
+++ b/test cases/rust/25 cargo lock/meson.build
@@ -0,0 +1,3 @@
+project('cargo lock')
+
+dependency('bar-0.1-rs')
diff --git a/test cases/rust/25 cargo lock/subprojects/packagecache/bar-0.1.tar.gz b/test cases/rust/25 cargo lock/subprojects/packagecache/bar-0.1.tar.gz
new file mode 100644
index 0000000..f4c2ec6
--- /dev/null
+++ b/test cases/rust/25 cargo lock/subprojects/packagecache/bar-0.1.tar.gz
diff --git a/unittests/cargotests.py b/unittests/cargotests.py
index f0aedd0..d1ac838 100644
--- a/unittests/cargotests.py
+++ b/unittests/cargotests.py
@@ -3,9 +3,12 @@
 
 from __future__ import annotations
 import unittest
+import os
+import tempfile
+import textwrap
 import typing as T
 
-from mesonbuild.cargo import builder, cfg
+from mesonbuild.cargo import builder, cfg, load_wraps
 from mesonbuild.cargo.cfg import TokenType
 from mesonbuild.cargo.version import convert
 
@@ -185,3 +188,34 @@ class CargoCfgTest(unittest.TestCase):
             with self.subTest():
                 value = cfg.ir_to_meson(cfg.parse(iter(cfg.lexer(data))), build)
                 self.assertEqual(value, expected)
+
+class CargoLockTest(unittest.TestCase):
+    def test_cargo_lock(self) -> None:
+        with tempfile.TemporaryDirectory() as tmpdir:
+            with open(os.path.join(tmpdir, 'Cargo.lock'), 'w', encoding='utf-8') as f:
+                f.write(textwrap.dedent('''\
+                    version = 3
+                    [[package]]
+                    name = "foo"
+                    version = "0.1"
+                    source = "registry+https://github.com/rust-lang/crates.io-index"
+                    checksum = "8a30b2e23b9e17a9f90641c7ab1549cd9b44f296d3ccbf309d2863cfe398a0cb"
+                    [[package]]
+                    name = "bar"
+                    version = "0.1"
+                    source = "git+https://github.com/gtk-rs/gtk-rs-core?branch=0.19#23c5599424cc75ec66618891c915d9f490f6e4c2"
+                    '''))
+            wraps = load_wraps(tmpdir, 'subprojects')
+            self.assertEqual(len(wraps), 2)
+            self.assertEqual(wraps[0].name, 'foo-0.1-rs')
+            self.assertEqual(wraps[0].directory, 'foo-0.1')
+            self.assertEqual(wraps[0].type, 'file')
+            self.assertEqual(wraps[0].get('method'), 'cargo')
+            self.assertEqual(wraps[0].get('source_url'), 'https://crates.io/api/v1/crates/foo/0.1/download')
+            self.assertEqual(wraps[0].get('source_hash'), '8a30b2e23b9e17a9f90641c7ab1549cd9b44f296d3ccbf309d2863cfe398a0cb')
+            self.assertEqual(wraps[1].name, 'bar-0.1-rs')
+            self.assertEqual(wraps[1].directory, 'bar')
+            self.assertEqual(wraps[1].type, 'git')
+            self.assertEqual(wraps[1].get('method'), 'cargo')
+            self.assertEqual(wraps[1].get('url'), 'https://github.com/gtk-rs/gtk-rs-core')
+            self.assertEqual(wraps[1].get('revision'), '23c5599424cc75ec66618891c915d9f490f6e4c2')