Use descriptor protocol for Param (#83)

- Converted Param to use descriptor protocol
- Added --destination to vsk save
- Updated all examples
- Added a test to run all examples
- vsk commands now have exit status of 1 on error condition

.github/pull_request_template.md

@@ -5,7 +5,7 @@
 #### Checklist
 
 - [ ] feature/fix implemented
-- [ ] `mypy vsketch tests` returns no error
+- [ ] `mypy` returns no error
 - [ ] tests added/updated and `pytest --runslow` succeeds
 - [ ] documentation added/updated and building with no error (`make clean && make html` in `docs/`)
 - [ ] examples added/updated

.gitignore

@@ -134,3 +134,4 @@ dmypy.json
 
 /mywork/
 /profile
+.idea

examples/bezier_bugs/sketch_bezier_bugs.py

@@ -42,10 +42,10 @@ class BezierBugSketch(vsketch.Vsketch):
     def draw(self) -> None:
         self.size("10in", "10in")
 
-        for row in range(self.row_count()):
-            for col in range(self.column_count()):
-                x = col * self.column_offset()
-                y = row * self.row_offset()
+        for row in range(self.row_count):
+            for col in range(self.column_count):
+                x = col * self.column_offset
+                y = row * self.row_offset
                 bug(self, x, y)
 
     def finalize(self) -> None:

examples/detail/sketch_detail.py

@@ -2,13 +2,13 @@
 
 
 class DetailSketch(vsketch.Vsketch):
-    detail_mm = vsketch.Param(1, 1, 50)
+    detail_value = vsketch.Param(1, 1, 50, unit="mm")
 
     def draw(self) -> None:
         self.size("a5", landscape=True)
         self.scale("1.5cm")
 
-        self.detail(f"{self.detail_mm()}mm")
+        self.detail(self.detail_value)
 
         self.circle(0, 0, 1)
         self.circle(0, 0, 2)

examples/noise_bezier/sketch_noise_bezier.py

@@ -10,9 +10,9 @@ def draw(self) -> None:
         self.size("a4", landscape=False)
         self.scale("cm")
 
-        for i in range(self.N()):
-            t = i * self.freq()
-            v = i * self.drift()
+        for i in range(self.N):
+            t = i * self.freq
+            v = i * self.drift
             self.bezier(
                 self.noise(t, 0) * 10 + v,
                 self.noise(t, 1000) * 10 + v,

examples/prime_circles/sketch_prime_circles.py

@@ -23,10 +23,10 @@ def draw(self) -> None:
         self.size("10in", "10in")
         self.scale("3mm")
 
-        for i, prime in enumerate(get_primes(self.N())):
+        for i, prime in enumerate(get_primes(self.N)):
             self.circle(0, 0, 2 * (i + 1))
 
-            if self.random_phase():
+            if self.random_phase:
                 phase = np.random.random() * 2 * math.pi
             else:
                 phase = -math.pi / 2

examples/quick_draw/sketch_quick_draw.py

@@ -417,11 +417,11 @@ class QuickDrawSketch(vsketch.Vsketch):
     scale_factor = vsketch.Param(3.0)
 
     def draw(self) -> None:
-        self.size(self.page_size(), landscape=self.landscape())
+        self.size(self.page_size, landscape=self.landscape)
         self.penWidth("0.5mm")
 
         # obtain the datafile
-        file_name = self.category() + ".bin"
+        file_name = self.category + ".bin"
         file_path = pathlib.Path(file_name)
         url = "https://storage.googleapis.com/quickdraw_dataset/full/binary/"
         url += file_name.replace(" ", "%20")
@@ -434,25 +434,23 @@ def draw(self) -> None:
 
         # draw stuff
 
-        width = self.width - 2 * self.margins()
-        height = self.height - 2 * self.margins()
+        width = self.width - 2 * self.margins
+        height = self.height - 2 * self.margins
 
-        n = self.columns() * self.rows()
+        n = self.columns * self.rows
         samples = random.sample(drawing_subset, n)
-        for j in range(self.rows()):
+        for j in range(self.rows):
             with self.pushMatrix():
-                for i in range(self.columns()):
-                    idx = j * self.columns() + i
+                for i in range(self.columns):
+                    idx = j * self.columns + i
                     with self.pushMatrix():
-                        self.scale(
-                            self.scale_factor() * min(1 / self.columns(), 1 / self.rows())
-                        )
+                        self.scale(self.scale_factor * min(1 / self.columns, 1 / self.rows))
                         drawing = quickdraw_to_linestring(samples[idx])
-                        self.stroke((idx % self.layer_count()) + 1)
+                        self.stroke((idx % self.layer_count) + 1)
                         self.geometry(drawing)
-                    self.translate(width / self.columns(), 0)
+                    self.translate(width / self.columns, 0)
 
-            self.translate(0, height / self.rows())
+            self.translate(0, height / self.rows)
 
     def finalize(self) -> None:
         self.vpype("linemerge linesort")

examples/random_flower/sketch_random_flower.py

@@ -16,17 +16,17 @@ def draw(self) -> None:
 
         self.rotate(-90, degrees=True)
 
-        noise_coord = np.linspace(0, 1, self.point_per_line())
+        noise_coord = np.linspace(0, 1, self.point_per_line)
 
-        dirs = np.linspace(0, 2 * math.pi, self.num_line())
+        dirs = np.linspace(0, 2 * math.pi, self.num_line)
 
         for direction in dirs:
             rdir = self.map(
                 np.array([self.noise(x, direction) for x in noise_coord]),
                 0,
                 1,
-                direction - self.rdir_range(),
-                direction + self.rdir_range(),
+                direction - self.rdir_range,
+                direction + self.rdir_range,
             )
             roffset = self.map(
                 np.array([self.noise(x, direction, 100) for x in noise_coord]),

examples/random_lines/sketch_random_lines.py

@@ -15,15 +15,15 @@ def draw(self) -> None:
 
         x_coords = np.linspace(0, 25, 1000)
 
-        for i in range(self.num_line()):
+        for i in range(self.num_line):
             y_coords = (
                 np.array(
                     [
-                        self.noise(x * self.x_freq(), i / self.num_line() * self.y_freq())
+                        self.noise(x * self.x_freq, i / self.num_line * self.y_freq)
                         for x in x_coords
                     ]
                 )
-                + self.y_offset() / self.num_line() * i
+                + self.y_offset / self.num_line * i
             )
             self.polygon(x_coords, y_coords)
 

examples/schotter/sketch_schotter.py

@@ -10,14 +10,14 @@ def draw(self) -> None:
         self.size("a4", landscape=False)
         self.scale("cm")
 
-        for j in range(self.rows()):
+        for j in range(self.rows):
             with self.pushMatrix():
-                for i in range(self.columns()):
+                for i in range(self.columns):
                     with self.pushMatrix():
-                        self.rotate(self.fuzziness() * 0.03 * self.random(-j, j))
+                        self.rotate(self.fuzziness * 0.03 * self.random(-j, j))
                         self.translate(
-                            self.fuzziness() * 0.01 * self.randomGaussian() * j,
-                            self.fuzziness() * 0.01 * self.randomGaussian() * j,
+                            self.fuzziness * 0.01 * self.randomGaussian() * j,
+                            self.fuzziness * 0.01 * self.randomGaussian() * j,
                         )
                         self.rect(0, 0, 1, 1)
                     self.translate(1, 0)

tests/test_examples.py

@@ -1,17 +1,31 @@
-import glob
 import pathlib
 
 import nbformat
 import pytest
 from nbconvert.preprocessors import ExecutePreprocessor
+from typer.testing import CliRunner
+from vsketch_cli.cli import cli
 
-EXAMPLES = str(pathlib.Path(__file__).parent.parent.absolute()) + "/examples/_notebooks/"
+EXAMPLES = pathlib.Path(__file__).parent.parent.absolute() / "examples"
+NOTEBOOKS = EXAMPLES / "_notebooks"
+
+runner = CliRunner()
 
 
 @pytest.mark.slow
-@pytest.mark.parametrize("ipynb", glob.glob(EXAMPLES + "*.ipynb"))
-def test_example_detail(tmp_path, ipynb):
+@pytest.mark.parametrize("ipynb", NOTEBOOKS.glob("*.ipynb"))
+def test_example_notebooks(tmp_path, ipynb):
     with open(ipynb) as f:
         nb = nbformat.read(f, as_version=4)
     ep = ExecutePreprocessor(timeout=600, kernel_name="python3")
     ep.preprocess(nb, {"metadata": {"path": tmp_path}})
+
+
+@pytest.mark.parametrize("path", EXAMPLES.glob("[!._]*[!.md]"))
+def test_examples(tmp_path, path):
+    # Note: split is needed to avoid `invoke`'s preprocessor to eat Windows' path backslashes
+    res = runner.invoke(
+        cli, f"save --name test_output --destination {tmp_path} {str(path)}".split()
+    )
+    assert res.exit_code == 0
+    assert (pathlib.Path(tmp_path) / "test_output.svg").exists()

tests/utils.py

@@ -11,7 +11,7 @@ def bounds_equal(
     """Asserts that sketch bounds are approximately equal to those provided"""
 
     bounds = vsk.document.bounds()
-    return (
+    return bool(
         bounds is not None
         and np.isclose(bounds[0], xmin, rtol=1e-03)
         and np.isclose(bounds[1], ymin, rtol=1e-03)

vsketch/param.py

@@ -101,7 +101,10 @@ def set_value_with_validation(self, v: Any) -> None:
 
         self.value = value
 
-    def __call__(self) -> ParamType:
+    def __get__(self, instance: Any, owner: Any = None) -> Any:
+        if instance is None:
+            return self
+
         if self.factor is None:
             return self.value
         else: