@@ -4,18 +4,39 @@ module.exports = wrap
44
55wrap . needed = needed
66
7+ var extend = require ( 'extend' )
78var phrasing = require ( 'mdast-util-phrasing' )
89
9- // Wrap all runs of mdast phrasing content in `paragraph` nodes.
1010function wrap ( nodes ) {
11+ return runs ( nodes , onphrasing )
12+
13+ function onphrasing ( nodes ) {
14+ var head = nodes [ 0 ]
15+
16+ if (
17+ nodes . length === 1 &&
18+ head . type === 'text' &&
19+ ( head . value === ' ' || head . value === '\n' )
20+ ) {
21+ return [ ]
22+ }
23+
24+ return { type : 'paragraph' , children : nodes }
25+ }
26+ }
27+
28+ // Wrap all runs of mdast phrasing content in `paragraph` nodes.
29+ function runs ( nodes , onphrasing , onnonphrasing ) {
30+ var nonphrasing = onnonphrasing || identity
1131 var result = [ ]
12- var length = nodes . length
32+ var flattened = flatten ( nodes )
33+ var length = flattened . length
1334 var index = - 1
1435 var node
1536 var queue
1637
1738 while ( ++ index < length ) {
18- node = nodes [ index ]
39+ node = flattened [ index ]
1940
2041 if ( phrasing ( node ) ) {
2142 if ( queue === undefined ) {
@@ -24,42 +45,114 @@ function wrap(nodes) {
2445
2546 queue . push ( node )
2647 } else {
27- flush ( )
28- result . push ( node )
48+ add ( )
49+ result = result . concat ( nonphrasing ( node ) )
2950 }
3051 }
3152
32- flush ( )
53+ add ( )
3354
3455 return result
3556
36- function flush ( ) {
57+ function add ( ) {
3758 if ( queue !== undefined ) {
38- if (
39- queue . length !== 1 ||
40- queue [ 0 ] . type !== 'text' ||
41- ( queue [ 0 ] . value !== ' ' && queue [ 0 ] . value !== '\n' )
42- ) {
43- result . push ( { type : 'paragraph' , children : queue } )
44- }
59+ result = result . concat ( onphrasing ( queue ) )
4560 }
4661
4762 queue = undefined
4863 }
4964}
5065
66+ // Flatten a list of nodes.
67+ function flatten ( nodes ) {
68+ var length = nodes . length
69+ var index = - 1
70+ var flattened = [ ]
71+ var node
72+
73+ while ( ++ index < length ) {
74+ node = nodes [ index ]
75+
76+ // Straddling: some elements are *weird*.
77+ // Namely: `map`, `ins`, `del`, and `a`, as they are hybrid elements.
78+ // See: <https://html.spec.whatwg.org/#paragraphs>.
79+ // Paragraphs are the weirdest of them all.
80+ // See the straddling fixture for more info!
81+ // `ins` is ignored in mdast, so we don’t need to worry about that.
82+ // `map` maps to its content, so we don’t need to worry about that either.
83+ // `del` maps to `delete` and `a` to `link`, so we do handle those.
84+ // What we’ll do is split `node` over each of its children.
85+ if (
86+ ( node . type === 'delete' || node . type === 'link' ) &&
87+ needed ( node . children )
88+ ) {
89+ flattened = flattened . concat ( split ( node ) )
90+ } else {
91+ flattened . push ( node )
92+ }
93+ }
94+
95+ return flattened
96+ }
97+
5198// Check if there are non-phrasing mdast nodes returned.
5299// This is needed if a fragment is given, which could just be a sentence, and
53100// doesn’t need a wrapper paragraph.
54101function needed ( nodes ) {
55102 var length = nodes . length
56103 var index = - 1
104+ var node
105+ var children
57106
58107 while ( ++ index < length ) {
59- if ( ! phrasing ( nodes [ index ] ) ) {
108+ node = nodes [ index ]
109+ children = node . children
110+
111+ if ( ! phrasing ( node ) || ( children && needed ( children ) ) ) {
60112 return true
61113 }
62114 }
63115
64116 return false
65117}
118+
119+ function split ( node ) {
120+ return runs ( node . children , onphrasing , onnonphrasing )
121+
122+ // Use `child`, add `parent` as its first child, put the original children
123+ // into `parent`.
124+ function onnonphrasing ( child ) {
125+ var parent = extend ( true , { } , shallow ( node ) )
126+ var copy = shallow ( child )
127+
128+ copy . children = [ parent ]
129+ parent . children = child . children
130+
131+ return copy
132+ }
133+
134+ // Use `parent`, put the phrasing run inside it.
135+ function onphrasing ( nodes ) {
136+ var parent = extend ( true , { } , shallow ( node ) )
137+ parent . children = nodes
138+ return parent
139+ }
140+ }
141+
142+ // Shallow copy of a node, excluding its children.
143+ function shallow ( node ) {
144+ var copy = { }
145+ var key
146+
147+ for ( key in node ) {
148+ if ( key !== 'children' ) {
149+ copy [ key ] = node [ key ]
150+ }
151+ }
152+
153+ return copy
154+ }
155+
156+ function identity ( n ) {
157+ return n
158+ }
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