Add wrapper to allow easy loading of yaml files.

Fixes #327.

Signed-off-by: Tim 'mithro' Ansell <me@mith.ro>

prjxray/xyaml.py

@@ -0,0 +1,65 @@
+#!/usr/bin/env python3
+import io
+import re
+import yaml
+import json
+import unittest
+
+
+def load(f):
+    data = f.read()
+    # Strip out of !<tags>
+    data = re.sub("!<[^>]*>", "", data)
+    return yaml.load(io.StringIO(data))
+
+
+def tojson(f):
+    d = load(f)
+    return json.dumps(d, sort_keys=True, indent=4)
+
+
+class XYamlTest(unittest.TestCase):
+    def test(self):
+        s = io.StringIO("""\
+!<xilinx/xc7series/part>
+idcode: 0x362d093
+global_clock_regions:
+  top: !<xilinx/xc7series/global_clock_region>
+    rows:
+      0: !<xilinx/xc7series/row>
+        configuration_buses:
+          CLB_IO_CLK: !<xilinx/xc7series/configuration_bus>
+            configuration_columns:
+              0: !<xilinx/xc7series/configuration_column>
+                frame_count: 42
+""")
+        djson = tojson(s)
+        self.assertMultiLineEqual(djson, """\
+{
+    "global_clock_regions": {
+        "top": {
+            "rows": {
+                "0": {
+                    "configuration_buses": {
+                        "CLB_IO_CLK": {
+                            "configuration_columns": {
+                                "0": {
+                                    "frame_count": 42
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    },
+    "idcode": 56807571
+}""")
+
+if __name__ == "__main__":
+    import sys
+    if len(sys.argv) == 1:
+        unittest.main()
+    else:
+        assert len(sys.argv) == 2
+        print(tojson(open(sys.argv[1])))