Break examples out of main workspace

As features are unified over the whole of a workspace, having the examples
inside the main workspace prevents independent tests of different combinations
of PyO3 features. Therefore, this PR breaks them out into separate workspaces
and adjust the xtask script to still include them where appropriate.

Author: adamreichold

.github/workflows/ci.yml

@@ -66,7 +66,7 @@ jobs:
         run: |
           import toml
           cargo_toml = toml.load("Cargo.toml")
-          cargo_toml["workspace"]["resolver"] = "2"
+          cargo_toml["package"]["resolver"] = "2"
           with open("Cargo.toml", "w") as f:
             toml.dump(cargo_toml, f)
         shell: python
@@ -116,14 +116,13 @@ jobs:
         continue-on-error: true
       - name: Install toml
         run: pip install toml
-      - name: Edit Cargo.toml and detach from workspace
+      - name: Edit Cargo.toml
         run: |
           import toml
           cargo_toml = toml.load("Cargo.toml")
           cargo_toml["dependencies"]["ndarray"] = "0.13.1"
           cargo_toml["dependencies"]["parking_lot"] = "0.11.2"
           cargo_toml["dependencies"]["num-complex"] = "0.2.4"
-          cargo_toml["workspace"] = {}
           with open("Cargo.toml", "w") as f:
             toml.dump(cargo_toml, f)
         working-directory: examples/simple

Cargo.toml

@@ -27,8 +27,5 @@ pyo3 = { version = "0.16", default-features = false, features = ["macros"] }
 [dev-dependencies]
 pyo3 = { version = "0.16", default-features = false, features = ["auto-initialize"] }
 
-[workspace]
-members = ["examples/*"]
-
 [package.metadata.docs.rs]
 all-features = true

examples/linalg/Cargo.toml

@@ -12,3 +12,5 @@ crate-type = ["cdylib"]
 pyo3 = { version = "0.16", features = ["extension-module"] }
 numpy = { path = "../.." }
 ndarray-linalg = { version = "0.14.1", features = ["openblas-system"] }
+
+[workspace]

examples/parallel/Cargo.toml

@@ -14,3 +14,5 @@ numpy = { path = "../.." }
 ndarray = { version = "0.15", features = ["rayon", "blas"] }
 blas-src = { version = "0.8", features = ["openblas"] }
 openblas-src = { version = "0.10", features = ["cblas", "system"] }
+
+[workspace]

examples/simple/Cargo.toml

@@ -11,3 +11,5 @@ crate-type = ["cdylib"]
 [dependencies]
 pyo3 = { version = "0.16", features = ["extension-module", "abi3-py37"] }
 numpy = { path = "../.." }
+
+[workspace]

x.py

@@ -24,13 +24,20 @@ def nightly():
     return b"-nightly " in proc.stdout
 
 
+def example_manifests(manifest):
+    return [dir_ / manifest for dir_ in Path("examples").iterdir()]
+
+
 def default(args):
-    run("cargo", "fmt")
+    format_(args)
 
     if nightly():
-        run("cargo", "clippy", "--workspace", "--all-features", "--tests", "--benches")
+        run("cargo", "clippy", "--all-features", "--tests", "--benches")
     else:
-        run("cargo", "clippy", "--workspace", "--all-features", "--tests")
+        run("cargo", "clippy", "--all-features", "--tests")
+
+    for manifest in example_manifests("Cargo.toml"):
+        run("cargo", "clippy", "--manifest-path", manifest)
 
     run("cargo", "test", "--all-features", "--lib", "--tests")
 
@@ -41,14 +48,18 @@ def check(args):
     run(
         "cargo",
         "clippy",
-        "--workspace",
         "--all-features",
         "--tests",
         "--",
         "--deny",
         "warnings",
     )
 
+    for manifest in example_manifests("Cargo.toml"):
+        run("cargo", "fmt", "--manifest-path", manifest, "--", "--check")
+
+        run("cargo", "clippy", "--manifest-path", manifest, "--", "--deny", "warnings")
+
 
 def doc(args):
     if args.name is None:
@@ -63,6 +74,8 @@ def doc(args):
 
 
 def test(args):
+    run("cargo", "test", "--all-features", "--lib")
+
     if args.name is None:
         run("cargo", "test", "--all-features", "--tests")
     else:
@@ -84,16 +97,10 @@ def examples(args):
         sys.exit("Examples require the Nox tool (https://nox.thea.codes)")
 
     if args.name is None:
-        dirs = [
-            dir_.name
-            for dir_ in Path("examples").iterdir()
-            if (dir_ / "noxfile.py").exists()
-        ]
+        for manifest in example_manifests("noxfile.py"):
+            run("nox", "--noxfile", manifest)
     else:
-        dirs = [args.name]
-
-    for dir in dirs:
-        run("nox", "--noxfile", f"examples/{dir}/noxfile.py")
+        run("nox", "--noxfile", f"examples/{args.name}/noxfile.py")
 
 
 def format_(args):
@@ -104,6 +111,9 @@ def format_(args):
 
     run("cargo", "fmt")
 
+    for manifest in example_manifests("Cargo.toml"):
+        run("cargo", "fmt", "--manifest-path", manifest)
+
     run("black", ".")