1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
|
require "cgi"
module Prism
# This visitor provides the ability to call Node#to_dot, which converts a
# subtree into a graphviz dot graph.
class DotVisitor < Visitor
class Field # :nodoc:
attr_reader :name, :value, :port
def initialize(name, value, port)
@name = name
@value = value
@port = port
end
def to_dot
if port
"<tr><td align=\"left\" colspan=\"2\" port=\"#{name}\">#{name}</td></tr>"
else
"<tr><td align=\"left\">#{name}</td><td>#{CGI.escapeHTML(value)}</td></tr>"
end
end
end
class Table # :nodoc:
attr_reader :name, :fields
def initialize(name)
@name = name
@fields = []
end
def field(name, value = nil, port: false)
fields << Field.new(name, value, port)
end
def to_dot
dot = <<~DOT
<table border="0" cellborder="1" cellspacing="0" cellpadding="4">
<tr><td colspan="2"><b>#{name}</b></td></tr>
DOT
if fields.any?
"#{dot} #{fields.map(&:to_dot).join("\n ")}\n</table>"
else
"#{dot}</table>"
end
end
end
class Digraph # :nodoc:
attr_reader :nodes, :waypoints, :edges
def initialize
@nodes = []
@waypoints = []
@edges = []
end
def node(value)
nodes << value
end
def waypoint(value)
waypoints << value
end
def edge(value)
edges << value
end
def to_dot
<<~DOT
digraph "Prism" {
node [
fontname=\"Courier New\"
shape=plain
style=filled
fillcolor=gray95
];
#{nodes.map { |node| node.gsub(/\n/, "\n ") }.join("\n ")}
node [shape=point];
#{waypoints.join("\n ")}
#{edges.join("\n ")}
}
DOT
end
end
private_constant :Field, :Table, :Digraph
# The digraph that is being built.
attr_reader :digraph
# Initialize a new dot visitor.
def initialize
@digraph = Digraph.new
end
# Convert this visitor into a graphviz dot graph string.
def to_dot
digraph.to_dot
end
<%- nodes.each do |node| -%>
# Visit a <%= node.name %> node.
def visit_<%= node.human %>(node)
table = Table.new("<%= node.name %>")
id = node_id(node)
<%- node.fields.each do |field| -%>
# <%= field.name %>
<%- case field -%>
<%- when Prism::NodeField -%>
table.field("<%= field.name %>", port: true)
digraph.edge("#{id}:<%= field.name %> -> #{node_id(node.<%= field.name %>)};")
<%- when Prism::OptionalNodeField -%>
unless (<%= field.name %> = node.<%= field.name %>).nil?
table.field("<%= field.name %>", port: true)
digraph.edge("#{id}:<%= field.name %> -> #{node_id(<%= field.name %>)};")
end
<%- when Prism::NodeListField -%>
if node.<%= field.name %>.any?
table.field("<%= field.name %>", port: true)
waypoint = "#{id}_<%= field.name %>"
digraph.waypoint("#{waypoint};")
digraph.edge("#{id}:<%= field.name %> -> #{waypoint};")
node.<%= field.name %>.each { |child| digraph.edge("#{waypoint} -> #{node_id(child)};") }
else
table.field("<%= field.name %>", "[]")
end
<%- when Prism::StringField, Prism::ConstantField, Prism::OptionalConstantField, Prism::UInt8Field, Prism::UInt32Field, Prism::ConstantListField -%>
table.field("<%= field.name %>", node.<%= field.name %>.inspect)
<%- when Prism::LocationField -%>
table.field("<%= field.name %>", location_inspect(node.<%= field.name %>))
<%- when Prism::OptionalLocationField -%>
unless (<%= field.name %> = node.<%= field.name %>).nil?
table.field("<%= field.name %>", location_inspect(<%= field.name %>))
end
<%- when Prism::FlagsField -%>
<%- flag = flags.find { |flag| flag.name == field.kind }.tap { |flag| raise "Expected to find #{field.kind}" unless flag } -%>
table.field("<%= field.name %>", <%= flag.human %>_inspect(node))
<%- else -%>
<%- raise -%>
<%- end -%>
<%- end -%>
digraph.nodes << <<~DOT
#{id} [
label=<#{table.to_dot.gsub(/\n/, "\n ")}>
];
DOT
super
end
<%- end -%>
private
# Generate a unique node ID for a node throughout the digraph.
def node_id(node)
"Node_#{node.object_id}"
end
# Inspect a location to display the start and end line and column numbers.
def location_inspect(location)
"(#{location.start_line},#{location.start_column})-(#{location.end_line},#{location.end_column})"
end
<%- flags.each do |flag| -%>
# Inspect a node that has <%= flag.human %> flags to display the flags as a
# comma-separated list.
def <%= flag.human %>_inspect(node)
flags = []
<%- flag.values.each do |value| -%>
flags << "<%= value.name.downcase %>" if node.<%= value.name.downcase %>?
<%- end -%>
flags.join(", ")
end
<%- end -%>
end
end
|
