Feature: lswap and lreverse commands

CHANGELOG.md

@@ -3,7 +3,8 @@
 #### 1.8 (UNRELEASED)
 
 New features and improvements:
-* ...
+* Added `lswap` command to swap the content of two layers (#300)
+* Added `lreverse` command to reverse the order of paths within a layer (#300)
 
 Bug fixes:
 * ...

README.md

@@ -172,7 +172,7 @@ and much more.
 #### General
 
 - Easy to use **CLI** interface with integrated help (`vpype --help`and `vpype COMMAND --help`) and support for arbitrary units (e.g. `vpype read input.svg translate 3cm 2in`).
-- First-class **multi-layer support** with global or per-layer processing (e.g. `vpype COMMANDNAME --layer 1,3`) and optionally-probabilistic layer edition commands ([`lmove`](https://vpype.readthedocs.io/en/stable/reference.html#lmove), [`lcopy`](https://vpype.readthedocs.io/en/stable/reference.html#lcopy), [`ldelete`](https://vpype.readthedocs.io/en/stable/reference.html#ldelete)).
+- First-class **multi-layer support** with global or per-layer processing (e.g. `vpype COMMANDNAME --layer 1,3`) and optionally-probabilistic layer edition commands ([`lmove`](https://vpype.readthedocs.io/en/stable/reference.html#lmove), [`lcopy`](https://vpype.readthedocs.io/en/stable/reference.html#lcopy), [`ldelete`](https://vpype.readthedocs.io/en/stable/reference.html#ldelete), [`lswap`](https://vpype.readthedocs.io/en/stable/reference.html#lswap), [`lreverse`](https://vpype.readthedocs.io/en/stable/reference.html#lreverse)).
 - Powerful hardware-accelerated **display** command with adjustable units, optional per-line coloring, optional pen-up trajectories display and per-layer visibility control ([`show`](https://vpype.readthedocs.io/en/stable/reference.html#show)).
 - Geometry **statistics** extraction ([`stat`](https://vpype.readthedocs.io/en/stable/reference.html#stat)).
 - Support for  **command history** recording (`vpype -H [...]`)

pyproject.toml

@@ -63,19 +63,19 @@ sphinx-rtd-theme = { version = "^0.5.0", optional = true }
 recommonmark = { version = ">=0.6,<0.8", optional = true }
 
 [tool.poetry.dev-dependencies]
-coverage = {extras = ["toml"], version = "^5.4"}
-pytest = "^6.2.3"
-pytest-cov = "^2.11.0"
-pytest-benchmark = "^3.2.3"
-black = "^21.5b1"
-isort = "^5.8.0"
+coverage = {extras = ["toml"], version = ">=5.4"}
+pytest = ">=6.2.3"
+pytest-cov = ">=2.11.0"
+pytest-benchmark = ">=3.2.3"
+black = ">=21.5b2"
+isort = ">=5.8.0"
 pyinstaller = "^4.3"
-packaging = "^20.8"
-pytest-mpl = "^0.12"
-mypy = "^0.901"
-types-cachetools = "^0.1.6"
-types-toml = "^0.1.1"
-types-pkg-resources = "^0.1.2"
+packaging = ">=20.8"
+pytest-mpl = ">=0.12"
+mypy = ">=0.901"
+types-cachetools = ">=0.1.6"
+types-toml = ">=0.1.1"
+types-pkg-resources = ">=0.1.2"
 
 [tool.poetry.extras]
 docs = ["Sphinx", "sphinx-click", "sphinx-autodoc-typehints", "sphinx-rtd-theme", "recommonmark"]

tests/test_commands.py

@@ -1,4 +1,5 @@
 import itertools
+from dataclasses import dataclass
 
 import numpy as np
 import pytest
@@ -12,45 +13,58 @@
 
 EXAMPLE_SVG = TESTS_DIRECTORY / "data" / "test_svg" / "svg_width_height" / "percent_size.svg"
 
+
+@dataclass
+class Command:
+    command: str
+    exit_code_no_layer: int
+    exit_code_one_layer: int
+    exit_code_two_layers: int
+
+
 MINIMAL_COMMANDS = [
-    "begin grid 2 2 line 0 0 10 10 end",
-    "begin repeat 2 line 0 0 10 10 end",
-    "frame",
-    "random",
-    "line 0 0 1 1",
-    "rect 0 0 1 1",
-    "arc 0 0 1 1 0 90",
-    "circle 0 0 1",
-    "ellipse 0 0 2 4",
-    f"read '{EXAMPLE_SVG}'",
-    f"read -m '{EXAMPLE_SVG}'",
-    "write -f svg -",
-    "write -f hpgl -d hp7475a -p a4 -",
-    "rotate 0",
-    "scale 1 1",
-    "scaleto 10cm 10cm",
-    "skew 0 0",
-    "translate 0 0",
-    "crop 0 0 1 1",
-    "linesort",
-    "linesort --two-opt",
-    "linemerge",
-    "linesimplify",
-    "multipass",
-    "reloop",
-    "lmove 1 new",
-    "lcopy 1 new",
-    "ldelete 1",
-    "trim 1mm 1mm",
-    "splitall",
-    "filter --min-length 1mm",
-    "pagesize 10inx15in",
-    "stat",
-    "snap 1",
-    "reverse",
-    "layout a4",
-    "squiggles",
-    "text 'hello wold'",
+    Command("begin grid 2 2 line 0 0 10 10 end", 0, 0, 0),
+    Command("begin repeat 2 line 0 0 10 10 end", 0, 0, 0),
+    Command("frame", 0, 0, 0),
+    Command("random", 0, 0, 0),
+    Command("line 0 0 1 1", 0, 0, 0),
+    Command("rect 0 0 1 1", 0, 0, 0),
+    Command("arc 0 0 1 1 0 90", 0, 0, 0),
+    Command("circle 0 0 1", 0, 0, 0),
+    Command("ellipse 0 0 2 4", 0, 0, 0),
+    Command(f"read '{EXAMPLE_SVG}'", 0, 0, 0),
+    Command(f"read -m '{EXAMPLE_SVG}'", 0, 0, 0),
+    Command("write -f svg -", 0, 0, 0),
+    Command("write -f hpgl -d hp7475a -p a4 -", 0, 0, 0),
+    Command("rotate 0", 0, 0, 0),
+    Command("scale 1 1", 0, 0, 0),
+    Command("scaleto 10cm 10cm", 0, 0, 0),
+    Command("skew 0 0", 0, 0, 0),
+    Command("translate 0 0", 0, 0, 0),
+    Command("crop 0 0 1 1", 0, 0, 0),
+    Command("linesort", 0, 0, 0),
+    Command("linesort --two-opt", 0, 0, 0),
+    Command("linemerge", 0, 0, 0),
+    Command("linesimplify", 0, 0, 0),
+    Command("multipass", 0, 0, 0),
+    Command("reloop", 0, 0, 0),
+    Command("lmove 1 new", 0, 0, 0),
+    Command("lcopy 1 new", 0, 0, 0),
+    Command("ldelete 1", 0, 0, 0),
+    Command("lswap 1 2", 2, 2, 0),
+    Command("lreverse 1", 0, 0, 0),
+    Command("line 0 0 10 10 lreverse 1", 0, 0, 0),
+    Command("random -l1 random -l2 lswap 1 2", 0, 0, 0),
+    Command("trim 1mm 1mm", 0, 0, 0),
+    Command("splitall", 0, 0, 0),
+    Command("filter --min-length 1mm", 0, 0, 0),
+    Command("pagesize 10inx15in", 0, 0, 0),
+    Command("stat", 0, 0, 0),
+    Command("snap 1", 0, 0, 0),
+    Command("reverse", 0, 0, 0),
+    Command("layout a4", 0, 0, 0),
+    Command("squiggles", 0, 0, 0),
+    Command("text 'hello wold'", 0, 0, 0),
 ]
 
 # noinspection SpellCheckingInspection
@@ -61,50 +75,54 @@
 )
 
 
-@pytest.mark.parametrize("args", MINIMAL_COMMANDS)
-def test_commands_empty_geometry(runner, args):
-    result = runner.invoke(cli, args, catch_exceptions=False)
-    assert result.exit_code == 0
+@pytest.mark.parametrize("cmd", MINIMAL_COMMANDS)
+def test_commands_empty_geometry(runner, cmd):
+    result = runner.invoke(cli, cmd.command, catch_exceptions=False)
+    assert result.exit_code == cmd.exit_code_no_layer
 
 
-@pytest.mark.parametrize("args", MINIMAL_COMMANDS)
-def test_commands_single_line(runner, args):
-    result = runner.invoke(cli, "line 0 0 10 10 " + args, catch_exceptions=False)
-    assert result.exit_code == 0
+@pytest.mark.parametrize("cmd", MINIMAL_COMMANDS)
+def test_commands_single_line(runner, cmd):
+    result = runner.invoke(cli, "line 0 0 10 10 " + cmd.command, catch_exceptions=False)
+    assert result.exit_code == cmd.exit_code_one_layer
 
 
-@pytest.mark.parametrize("args", MINIMAL_COMMANDS)
-def test_commands_degenerate_line(runner, args):
-    result = runner.invoke(cli, "line 0 0 0 0 " + args)
-    assert result.exit_code == 0
+@pytest.mark.parametrize("cmd", MINIMAL_COMMANDS)
+def test_commands_degenerate_line(runner, cmd):
+    result = runner.invoke(cli, "line 0 0 0 0 " + cmd.command)
+    assert result.exit_code == cmd.exit_code_one_layer
 
 
-@pytest.mark.parametrize("args", MINIMAL_COMMANDS)
-def test_commands_random_input(runner, args):
-    result = runner.invoke(cli, "random -n 100 " + args)
-    assert result.exit_code == 0
+@pytest.mark.parametrize("cmd", MINIMAL_COMMANDS)
+def test_commands_random_input(runner, cmd):
+    result = runner.invoke(cli, "random -n 100 " + cmd.command)
+    assert result.exit_code == cmd.exit_code_one_layer
 
 
 @pytest.mark.parametrize("args", MINIMAL_COMMANDS)
 def test_commands_execute(args):
-    execute(args)
+    if args.exit_code_no_layer == 0:
+        execute(args.command)
 
 
-@pytest.mark.parametrize("args", MINIMAL_COMMANDS)
-def test_commands_must_return_document(runner, args):
+@pytest.mark.parametrize("cmd", MINIMAL_COMMANDS)
+def test_commands_must_return_document(runner, cmd):
     @cli.command()
     @vp.global_processor
     def assertdoc(document):
         assert document is not None
         assert type(document) is vp.Document
 
-    result = runner.invoke(cli, "line 0 0 10 10 " + args + " assertdoc")
-    assert result.exit_code == 0
+    result = runner.invoke(cli, "line 0 0 10 10 " + cmd.command + " assertdoc")
+    assert result.exit_code == cmd.exit_code_one_layer
 
 
-@pytest.mark.parametrize("args", MINIMAL_COMMANDS)
-def test_commands_keeps_page_size(runner, args):
+@pytest.mark.parametrize("cmd", MINIMAL_COMMANDS)
+def test_commands_keeps_page_size(runner, cmd):
     """No command shall "forget" the current page size, unless its `pagesize` of course."""
+
+    args = cmd.command
+
     if args.split()[0] in ["pagesize", "layout"]:
         return
 
@@ -117,8 +135,10 @@ def getpagesize(doc: vp.Document) -> vp.Document:
         page_size = doc.page_size
         return doc
 
-    result = runner.invoke(cli, "pagesize --landscape 5432x4321 " + args + " getpagesize")
-    assert result.exit_code == 0
+    result = runner.invoke(
+        cli, "random random -l2 pagesize --landscape 5432x4321 " + args + " getpagesize"
+    )
+    assert result.exit_code == cmd.exit_code_two_layers
     assert page_size == (5432, 4321)
 
 
@@ -449,7 +469,7 @@ def test_snap_no_duplicate(pitch: float):
 def test_splitall_filter_duplicates(line, expected):
     lc = execute_single_line("splitall", line)
 
-    assert np.all(l == el for l, el in zip(lc, expected))
+    assert np.all(line == expected_line for line, expected_line in zip(lc, expected))
 
 
 @pytest.mark.parametrize(

tests/test_layers.py

@@ -2,6 +2,8 @@
 import math
 import random
 
+import click
+import numpy as np
 import pytest
 
 import vpype as vp
@@ -28,6 +30,9 @@
         ("line 0 0 1 1 lmove all new", [2]),
         ("line 0 0 1 1 line -l new 0 0 1 1 lmove all 2", [2]),
         ("line 0 0 1 1 line -l new 0 0 1 1 lmove all 3", [3]),
+        ("line 0 0 1 1 lreverse 1", [1]),
+        ("lreverse 1", []),  # lreverse doesnt create phantom layers
+        ("line -l2 0 0 1 1 lreverse 1", [2]),
     ],
 )
 def test_layer_creation(runner, command, layers):
@@ -83,6 +88,12 @@ def big_doc():
     return doc
 
 
+def test_layer_not_new():
+    with pytest.raises(click.exceptions.BadParameter) as exc:
+        execute("ldelete new")
+    assert "existing" in exc.value.message
+
+
 def test_lmove(big_doc):
     doc = execute("lmove 1 2", big_doc)
 
@@ -176,3 +187,24 @@ def test_lcopy_prob_zero(big_doc):
 
     assert len(doc.layers[1]) == 1000
     assert 2 not in doc.layers
+
+
+def test_lswap():
+    doc = execute("line -l1 0 0 10 10 line -l2 20 20 30 30 lswap 1 2")
+
+    assert np.all(doc.layers[1][0] == np.array([20 + 20j, 30 + 30j]))
+    assert np.all(doc.layers[2][0] == np.array([0, 10 + 10j]))
+
+
+def test_lswap_prob_zero():
+    doc = execute("line -l1 0 0 10 10 line -l2 20 20 30 30 lswap --prob 0. 1 2")
+
+    assert np.all(doc.layers[2][0] == np.array([20 + 20j, 30 + 30j]))
+    assert np.all(doc.layers[1][0] == np.array([0, 10 + 10j]))
+
+
+def test_lreverse():
+    doc = execute("line 0 0 10 10 line 20 20 30 30 lreverse 1")
+
+    assert np.all(doc.layers[1][0] == np.array([20 + 20j, 30 + 30j]))
+    assert np.all(doc.layers[1][1] == np.array([0, 10 + 10j]))

vpype/layers.py

@@ -51,13 +51,16 @@ def multiple_to_layer_ids(
         return []
 
 
-def single_to_layer_id(layer: Optional[int], document: Document) -> int:
+def single_to_layer_id(
+    layer: Optional[int], document: Document, must_exist: bool = False
+) -> int:
     """Convert single-layer CLI argument to layer ID, accounting for the existence of a current
     a current target layer and dealing with default behavior.
 
     Arg:
         layer: value from a :class:`LayerType` argument
         document: target :class:`Document` instance (for new layer ID)
+        must_exists: if True, the function
 
     Returns:
         Target layer ID
@@ -71,6 +74,9 @@ def single_to_layer_id(layer: Optional[int], document: Document) -> int:
     else:
         lid = layer
 
+    if must_exist and lid not in document.layers:
+        raise click.BadParameter(f"layer {layer} does not exist")
+
     return lid
 
 
@@ -113,12 +119,22 @@ def convert(self, value, param, ctx):
             if self.accept_multiple:
                 return LayerType.ALL
             else:
-                self.fail("'all' was not expected", param, ctx)
+                self.fail(
+                    f"parameter {param.human_readable_name} must be a single layer and does "
+                    "not accept `all`",
+                    param,
+                    ctx,
+                )
         elif value.lower() == "new":
             if self.accept_new:
                 return LayerType.NEW
             else:
-                self.fail("'new' was not expected", param, ctx)
+                self.fail(
+                    f"parameter {param.human_readable_name} must be an existing layer and "
+                    "does not accept `new`",
+                    param,
+                    ctx,
+                )
 
         try:
             if self.accept_multiple:
@@ -132,4 +148,8 @@ def convert(self, value, param, ctx):
         except TypeError:
             self.fail(f"unexpected {value!r} of type {type(value).__name__}", param, ctx)
         except ValueError:
-            self.fail(f"{value!r} is not a valid value", param, ctx)
+            self.fail(
+                f"{value!r} is not a valid value for parameter {param.human_readable_name}",
+                param,
+                ctx,
+            )