dev: add script to visualize pikchr syntax tree

pikchr/syntax_tree.py

@@ -0,0 +1,124 @@
+#!/usr/bin/env python3
+import re
+from collections import defaultdict
+import graphviz
+from argparse import ArgumentParser
+
+
+def parse(filename: str):
+    with open(filename) as f:
+        code = f.read()
+        no_paren = re.compile(r"\(.+\)", re.MULTILINE | re.DOTALL)
+        spaces = re.compile(r"\s+", re.MULTILINE | re.DOTALL)
+        for left, right in re.findall(
+            r"^\s*(\S+)\s*::=(.*?)\.", code, re.MULTILINE | re.DOTALL
+        ):
+            left = no_paren.sub("", left)
+            right = [
+                no_paren.sub("", item) for item in spaces.split(right.strip())
+            ]
+            yield left, right
+
+
+subgraphs = (
+    "basetype",
+    "between",
+    "boolproperty",
+    "colorproperty",
+    "dashproperty",
+    "direction",
+    "edge",
+    "even",
+    "lvalue",
+    "numproperty",
+    "print",
+    "pritem",
+    "prsep",
+    "rvalue",
+    "savelist",
+    "unnamed_statement",
+    "withclause",
+    "optrelexpr",
+    # "objectname", recursion
+)
+
+dbg_count = 0
+
+
+def render(
+    dot: graphviz.Digraph,
+    dot_key: str,
+    items: list[str],
+    dd: dict[str, list[list[str]]],
+):
+    global dbg_count
+    prev = dot_key
+    replace = {
+        "EOL": r"\\n|;",
+        "": r"\<empty string\>",
+        "EDGEPT": "bot|c|e|east|n|ne|north|nw|s|se|south|sw|w|west",
+        "LAST": "last|previous",
+        "PERCENT": "%",
+        "LP": "(",
+        "RP": ")",
+        "LB": "[",
+        "RB": "]",
+        "COMMA": ",",
+        "COLON": ":",
+        "GT": ">",
+        "LT": "<",
+        "EQ": "=",
+        "PLUS": "+",
+        "MINUS": "-",
+        "LRARROW": "\\<-\\>",
+        "LARROW": "\\<-",
+        "RARROW": "-\\>",
+        "PLACENAME": "PLACENAME ([A-Z]+)",
+        "CLASSNAME": "arc|arrow|box|circle|cylinder|dot|ellipse|file|line|move|oval|spline|text",
+        "even": r"UNTIL EVEN WITH|EVEN WITH",
+    }
+    for orig_value in items:
+        dbg_count += 1
+        dot2_key = f"{orig_value}_{dot_key}_{dbg_count}"
+        value = replace.get(orig_value, orig_value)
+        if value in enumerate(subgraphs):
+            dot2_key = f"{value}_{dot_key}_{dbg_count}"
+            with dot.subgraph(
+                name=dot2_key,
+                comment=value,
+                node_attr={"shape": "box", "color": "green", "label": value},
+            ) as c:
+                for item in dd[value]:
+                    render(c, dot2_key, item, dd)
+        else:
+            if value.isupper() or orig_value in replace:
+                color = "red"
+            else:
+                color = "blue"
+            dot.node(dot2_key, value, color=color)
+        dot.edge(prev, dot2_key)
+        prev = dot2_key
+
+
+def main():
+    parser = ArgumentParser()
+    parser.add_argument("pikchr_y_path")
+    pikchr_y_path = parser.parse_args().pikchr_y_path
+    dot = graphviz.Digraph("round-table", comment="Pikchr")
+    dd = defaultdict[str, list[list[str]]](list)
+    for left, right in parse(pikchr_y_path):
+        dd[left].append(right)
+
+    for idx, (key, items) in enumerate(dd.items()):
+        if key in subgraphs:
+            continue
+        dot_key = f"{key}_{idx}"
+        dot.node(dot_key, key)
+        for item in items:
+            render(dot, dot_key, item, dd)
+
+    dot.render(directory="doctest-output", view=True)
+
+
+if __name__ == "__main__":
+    main()