SwiftUI View Tree Graph

viewtree.py

#!/opt/homebrew/bin/python3

import re
import glob
import os
import graphviz
import sys

## USAGE #########################################################################

# 1. Install
#   brew install python3
#   pip install graphviz

# 2. Set this to the name of your main SwiftUI view file
MAIN_FILE = 'RootView.swift'

# 4. Call passing the folder containing your sources, e.g.
#   python3 viewtree.py Sources/Application

os.environ["PATH"] += os.pathsep +  "/opt/homebrew/bin"

# Ignore any `PreferenceKey` and `EnvironmentKey` types
DROP_KEYS = True

# Ignore anything that isn't a `View`
DROP_NON_VIEWS = True

# Style subgraphs differently
STYLE_SUBGRAPH = False

##################################################################################

class Node:
    def __init__(self, name, children, inline_children):
        self.name = name
        self.children = children
        self.inline_children = inline_children

found = []

def find_main_file(folder, main_file_name):
    for root, dirs, files in os.walk(folder):
        if main_file_name in files:
            return os.path.join(root, main_file_name)
    return None

def analyze(file, folder):
    base = os.path.basename(file)
    if DROP_NON_VIEWS and not base.endswith("View.swift"):
        return None

    found.append(file)
    base = os.path.basename(file)
    viewname = os.path.splitext(base)[0]
    
    children = []
    inline_structs = []
    
    with open(file) as f:
        lines = f.readlines()
    
    for rawline in lines:
        line = rawline.strip()
        if line.strip("private").strip("public").strip().startswith("struct"):
            regex_result = re.search("struct ([A-Za-z0-9_]*)", line)
            if regex_result:
                name = regex_result.group(1)
                if name != viewname and name not in inline_structs and "_" not in name:
                    isView = "View" in line
                    if not DROP_NON_VIEWS or isView:
                        iskey = "PreferenceKey" in line or "EnvironmentKey" in line
                        if not DROP_KEYS or not iskey:
                            inline_structs.append(name)
    
    in_view = False
    
    for rawline in lines:
        line = rawline.strip()
        is_comment = line.startswith("/*") or line.startswith("*") or line.startswith("//") or line.startswith("import")
        is_property_decl = " var " in line or " let " in line
        if not is_comment and not is_property_decl:
            regex_result = re.search(r"(?!\.)([A-Z][a-zA-z0-9]*)(?!\.)\s*(\(|{)", line)
            if regex_result:
                name = regex_result.group(1)
                if name not in inline_structs and "_" not in name:
                    for f in glob.glob(os.path.join(folder, '**/' + name + '.swift'), recursive=True):
                        if f != file:
                            child = analyze(f, folder)
                            children.append(child)
    
    return Node(viewname, children, inline_structs)

# keep track of already created edges since we don't care about multiple edges between the same nodes
edgesIDs = [] 

def graph(dot, node):
    if node is None:
        return

    dot.node(node.name)

    for child in node.children:
        if child is not None:
            id = node.name + child.name
            if id not in edgesIDs:
                edgesIDs.append(id)
                dot.edge(node.name, child.name)
                graph(dot, child)
        else:
            continue

    if len(node.inline_children) > 0:
        with dot.subgraph(name='cluster_' + node.name) as c:
            if STYLE_SUBGRAPH:
                c.node_attr['shape'] = 'egg'
                c.node_attr['fontcolor'] = 'darkgray'
                c.node_attr['style'] = ''
            c.graph_attr['style'] = 'dotted'
            
            for inline in node.inline_children:
                id = node.name + inline
                if id not in edgesIDs:
                    edgesIDs.append(id)
                    c.node(inline)
                    c.edge(node.name, inline)

def run():
    if len(sys.argv) != 2:
        print("Usage: script.py <folder>")
        sys.exit(1)
    
    folder = sys.argv[1]
    main_file_path = find_main_file(folder, MAIN_FILE)
    
    if not main_file_path:
        print(f"Error: {MAIN_FILE} not found in {folder}")
        sys.exit(1)

    main_node = analyze(main_file_path, folder)
    if main_node is None:
        print("No valid View-based main file found.")
        return

    dot = graphviz.Digraph(comment='View Tree From: ' + main_node.name, node_attr={'shape': 'box', 'style': 'filled'})
    graph(dot, main_node)
    if STYLE_SUBGRAPH:
        source = dot
    else:
        source = dot.unflatten(stagger=3)

    # uncomment this to keep the dot file. Dot files can be edited in Omnigraffle.
    # dot.save('./swiftui-views.dot')

    source.render('./swiftui-views', format='png', view=True)

    if os.path.exists('./swiftui-views'):
        os.remove('./swiftui-views')

run()

Changes

• Pass a path to source folder as first parameter
• Find the root view file set in MAIN_FILE
• When DROP_NON_VIEWS = True (default) ignore files whose filename is not suffixed with View.swift
• Remove intermediate digraph file at the end
• Rename generated file to swiftui-views.png
• Add commented line to save a .dot file
• Remove printing the nodes to console