Fix svg exporting

pcbdl/netlistsvg.py

@@ -17,6 +17,7 @@
 import pcbdl.small_parts as small_parts
 
 import collections
+import logging
 import json
 import os
 import re
@@ -274,7 +275,7 @@ def add_parts(self, indent_depth=""):
             "type": self.svg_type
         }
 
-        print(indent_depth + str(part))
+        logging.debug(f"Added part to SVG: {indent_depth + str(part)}")
 
         # Make sure the other related parts are squeezed on this page
         for other_part in parts_to_bring_on_page:
@@ -355,7 +356,7 @@ def generate(self):
                 "-o",
                 netlistsvg_output.name
             ]
-            print(netlistsvg_command)
+            logging.debug(f"Called SVG with command: {netlistsvg_command}")
             subprocess.call(netlistsvg_command)
 
             svg_contents = netlistsvg_output.read()
@@ -368,7 +369,24 @@ def generate(self):
         return svg_contents
 
 
-def generate_svg(*args, **kwargs):
+def generate_svg(filename: str, *args, multi_filename_ending: str="_{0}", **kwargs):
+    """Generates an SVG or a series of SVG files to a given file. If multiple
+    SVG pages are created, then each SVG is named according to the scheme
+    'filename'+'multi_filename_ending'.format(i) where i is the page number.
+
+    Args:
+        filename: The file name to write the SVG to. If multiple SVGs are written
+            then the multi_filename_ending will be concatenated.
+        multi_filename_ending: The ending to concatenate to filename in order to
+            name multiple generated SVG files sequentially. The ending is
+            evaluated like 'multi_filename_ending'.format(i) where i is the page
+            number. Defaults to "_{0}".
+    """
+    # Force SVG file
+    if not filename.lower().endswith(('.svg')):
+        filename += ".svg"
+
+    svg_arr = []
     pins_to_skip = []
     while True:
         n = SVGPage(*args, **kwargs, pins_to_skip=pins_to_skip)
@@ -378,4 +396,17 @@ def generate_svg(*args, **kwargs):
             break
         pins_to_skip += n.pins_drawn
 
-        yield svg_contents
+        svg_arr.append(svg_contents)
+
+    # Write a single file with the SVG name
+    assert len(svg_arr) > 0, "No SVG generated, check inputs."
+    if len(svg_arr) == 1:
+        with open(filename, "w") as svg_file:
+            svg_file.write(svg_arr[0])
+        logging.info(f"Wrote SVG file: {filename}")
+    if len(svg_arr) > 1:
+        for i, svg in enumerate(svg_arr):
+            svg_filename = filename + multi_filename_ending.format(i)
+            with open(svg_filename, "w") as svg_file:
+                svg_file.write(svg)
+            logging.info(f"Wrote SVG file: {svg_filename}")

test/svg_test.py

@@ -0,0 +1,84 @@
+import unittest
+import os
+import glob
+
+from pcbdl import *
+
+class SVGTest(unittest.TestCase):
+
+    @classmethod
+    def setUpClass(cls):
+        super().setUpClass()
+        cls.ac_coupling_value = "1000u"
+        cls.subcircuit_id = 0
+        cls.vcc, cls.gnd = Net("vcc"), Net("gnd")
+
+    def _add_sub_circuit(self):
+        """Adds a simple sub-circuit to the schematic, naming local subnets
+        with a convention based on an incrementing id.
+        """
+        transistor = BJT("2n3904")
+
+        C = C_POL
+
+        transistor.BASE << (
+            C(self.ac_coupling_value, to=Net(f"vin_{self.subcircuit_id}")),
+            R("1k", to=self.vcc),
+            R("1k", to=self.gnd),
+        )
+
+        transistor.COLLECTOR << (
+            C(self.ac_coupling_value, to=Net(f"vout_{self.subcircuit_id}")),
+            R("100", to=self.vcc),
+        )
+
+        transistor.EMITTER << (
+            R("100",  to=self.gnd),
+            C("1u",  to=self.gnd),
+        )
+
+        SVGTest.subcircuit_id += 1
+
+
+    def test_empty_page_write(self):
+        """Ensure that an AssertionError is created when no objects exist
+        to write to an SVG
+        """
+        self.assertRaises(AssertionError, generate_svg, "test")
+
+    def test_single_page_write(self):
+        """Ensure a SVG is generated when a sub circuit is added, and then
+        delete the SVG file.
+        """
+        # TODO: Ensure that this works on Windows which doesn't have a tmp
+        # directory
+        self._add_sub_circuit()
+        file_name = "/tmp/test"
+        generate_svg(file_name)
+        gen_filename = file_name + ".svg"
+        self.assertTrue(os.path.isfile(gen_filename), "SVG was not generated")
+        os.remove(gen_filename)
+
+    def test_multi_page_write(self):
+        """Generates a large circuit and tests whether multiple SVG pages are
+        created.
+        """
+        # Should be enough sub-circuits to trigger multi-page writing.
+        for _ in range(100):
+            self._add_sub_circuit()
+
+        file_name = "/tmp/test"
+        multi_filename_ending = "_{0}"
+        generate_svg(file_name, multi_filename_ending=multi_filename_ending)
+        gen_filename = file_name + multi_filename_ending.format(0) + ".svg"
+        self.assertTrue(os.path.isfile(gen_filename), 
+            "Multiple SVGs were not generated.")
+
+        rem_files = glob.glob(file_name + "*.svg", recursive=True)
+        # Remove all generated files
+        for rem_file in rem_files:
+            os.remove(rem_file)
+
+
+if __name__ == "__main__":
+    unittest.main()