Add support for multi-constraints dependencies (#406)

docs/docs/versions.md

@@ -128,3 +128,26 @@ pathlib2 = { version = "^2.2", python = "~2.7" }
 [tool.poetry.dependencies]
 pathlib2 = { version = "^2.2", python = ["~2.7", "^3.2"] }
 ```
+
+
+### Multiple constraints dependencies
+
+Sometimes, one of your dependency may have different version ranges depending
+on the target Python versions.
+
+Let's say you have a dependency on the package `foo` which is only compatible
+with Python <3.0 up to version 1.9 and compatible with Python 3.4+ from version 2.0:
+you would declare it like so:
+
+```toml
+[tool.poetry.dependencies]
+foo = [
+    {version = "<=1.9", python = "^2.7"},
+    {version = "^2.0", python = "^3.4"}
+]
+```
+
+!!!note
+
+    The constraints **must** have different requirements (like `python`)
+    otherwise it will cause an error when resolving dependencies.

poetry/json/schemas/poetry-schema.json

@@ -183,6 +183,9 @@
                         },
                         {
                             "$ref": "#/definitions/path-dependency"
+                        },
+                        {
+                            "$ref": "#/definitions/multiple-constraints-dependency"
                         }
                     ]
                 }
@@ -345,6 +348,29 @@
                 }
             }
         },
+        "multiple-constraints-dependency": {
+            "type": "array",
+            "minItems": 1,
+            "items": {
+                "oneOf": [
+                    {
+                        "$ref": "#/definitions/dependency"
+                    },
+                    {
+                        "$ref": "#/definitions/long-dependency"
+                    },
+                    {
+                        "$ref": "#/definitions/git-dependency"
+                    },
+                    {
+                        "$ref": "#/definitions/file-dependency"
+                    },
+                    {
+                        "$ref": "#/definitions/path-dependency"
+                    }
+                ]
+            }
+        },
         "repository": {
             "type": "object",
             "properties": {

poetry/poetry.py

@@ -120,10 +120,22 @@ class Poetry:
                     package.python_versions = constraint
                     continue
 
+                if isinstance(constraint, list):
+                    for _constraint in constraint:
+                        package.add_dependency(name, _constraint)
+
+                    continue
+
                 package.add_dependency(name, constraint)
 
         if "dev-dependencies" in local_config:
             for name, constraint in local_config["dev-dependencies"].items():
+                if isinstance(constraint, list):
+                    for _constraint in constraint:
+                        package.add_dependency(name, _constraint)
+
+                    continue
+
                 package.add_dependency(name, constraint, category="dev")
 
         extras = local_config.get("extras", {})

tests/fixtures/project_with_multi_constraints_dependency/pyproject.toml

+[tool.poetry]
+name = "project-with-multi-constraints-dependency"
+version = "1.2.3"
+description = "This is a description"
+authors = ["Your Name <you@example.com>"]
+license = "MIT"
+
+packages = [
+    {include = "project"}
+]
+
+[tool.poetry.dependencies]
+python = "*"
+pendulum = [
+    { version = "^1.5", python = "<3.4" },
+    { version = "^2.0", python = "^3.4" }
+]
+
+[tool.poetry.dev-dependencies]

tests/masonry/builders/test_sdist.py

@@ -197,6 +197,45 @@ def test_find_files_to_add():
     )
 
 
+def test_make_pkg_info_multi_constraints_dependency():
+    poetry = Poetry.create(
+        Path(__file__).parent.parent.parent
+        / "fixtures"
+        / "project_with_multi_constraints_dependency"
+    )
+
+    builder = SdistBuilder(poetry, NullEnv(), NullIO())
+    pkg_info = builder.build_pkg_info()
+    p = Parser()
+    parsed = p.parsestr(to_str(pkg_info))
+
+    requires = parsed.get_all("Requires-Dist")
+    assert requires == [
+        'pendulum (>=1.5,<2.0); python_version < "3.4"',
+        'pendulum (>=2.0,<3.0); python_version >= "3.4" and python_version < "4.0"',
+    ]
+
+
+def test_find_files_to_add():
+    poetry = Poetry.create(project("complete"))
+
+    builder = SdistBuilder(poetry, NullEnv(), NullIO())
+    result = builder.find_files_to_add()
+
+    assert sorted(result) == sorted(
+        [
+            Path("LICENSE"),
+            Path("README.rst"),
+            Path("my_package/__init__.py"),
+            Path("my_package/data1/test.json"),
+            Path("my_package/sub_pkg1/__init__.py"),
+            Path("my_package/sub_pkg2/__init__.py"),
+            Path("my_package/sub_pkg2/data2/data.json"),
+            Path("pyproject.toml"),
+        ]
+    )
+
+
 def test_find_packages():
     poetry = Poetry.create(project("complete"))
 

tests/test_poetry.py

@@ -123,6 +123,16 @@ def test_poetry_with_packages_and_includes():
     assert package.include == ["extra_dir/vcs_excluded.txt", "notes.txt"]
 
 
+def test_poetry_with_multi_constraints_dependency():
+    poetry = Poetry.create(
+        str(fixtures_dir / "project_with_multi_constraints_dependency")
+    )
+
+    package = poetry.package
+
+    assert len(package.requires) == 2
+
+
 def test_check():
     complete = TomlFile(fixtures_dir / "complete.toml")
     content = complete.read()["tool"]["poetry"]