fix: table after paragraph without blank line (#2298)

* fix: gfm table requires leading empty line

* test(gfm/table): add some test cases

* revert changes to `gfm.0.29.json`

* test(gfm/table): add `table_following_text` testcase

Author: EmmetZC

src/rules.js

@@ -30,7 +30,7 @@ export const block = {
   lheading: /^([^\n]+)\n {0,3}(=+|-+) *(?:\n+|$)/,
   // regex template, placeholders will be replaced according to different paragraph
   // interruption rules of commonmark and the original markdown spec:
-  _paragraph: /^([^\n]+(?:\n(?!hr|heading|lheading|blockquote|fences|list|html| +\n)[^\n]+)*)/,
+  _paragraph: /^([^\n]+(?:\n(?!hr|heading|lheading|blockquote|fences|list|html|table| +\n)[^\n]+)*)/,
   text: /^[^\n]+/
 };
 
@@ -69,6 +69,7 @@ block.paragraph = edit(block._paragraph)
   .replace('hr', block.hr)
   .replace('heading', ' {0,3}#{1,6} ')
   .replace('|lheading', '') // setex headings don't interrupt commonmark paragraphs
+  .replace('|table', '')
   .replace('blockquote', ' {0,3}>')
   .replace('fences', ' {0,3}(?:`{3,}(?=[^`\\n]*\\n)|~{3,})[^\\n]*\\n')
   .replace('list', ' {0,3}(?:[*+-]|1[.)]) ') // only lists starting from 1 can interrupt
@@ -107,6 +108,17 @@ block.gfm.table = edit(block.gfm.table)
   .replace('tag', block._tag) // tables can be interrupted by type (6) html blocks
   .getRegex();
 
+block.gfm.paragraph = edit(block._paragraph)
+  .replace('hr', block.hr)
+  .replace('heading', ' {0,3}#{1,6} ')
+  .replace('|lheading', '') // setex headings don't interrupt commonmark paragraphs
+  .replace('table', block.gfm.table) // interrupt paragraphs with table
+  .replace('blockquote', ' {0,3}>')
+  .replace('fences', ' {0,3}(?:`{3,}(?=[^`\\n]*\\n)|~{3,})[^\\n]*\\n')
+  .replace('list', ' {0,3}(?:[*+-]|1[.)]) ') // only lists starting from 1 can interrupt
+  .replace('html', '</?(?:tag)(?: +|\\n|/?>)|<(?:script|pre|style|textarea|!--)')
+  .replace('tag', block._tag) // pars can be interrupted by type (6) html blocks
+  .getRegex();
 /**
  * Pedantic grammar (original John Gruber's loose markdown specification)
  */

test/specs/new/table_following_text.html

@@ -0,0 +1,38 @@
+<p>hello world</p>
+<table>
+    <thead>
+    <tr>
+        <th>abc</th>
+        <th>def</th>
+    </tr>
+    </thead>
+    <tbody>
+    <tr>
+        <td>bar</td>
+        <td>foo</td>
+    </tr>
+    <tr>
+        <td>baz</td>
+        <td>boo</td>
+    </tr>
+    </tbody>
+</table>
+<p>hello world with empty line</p>
+<table>
+    <thead>
+    <tr>
+        <th>abc</th>
+        <th>def</th>
+    </tr>
+    </thead>
+    <tbody>
+    <tr>
+        <td>bar</td>
+        <td>foo</td>
+    </tr>
+    <tr>
+        <td>baz</td>
+        <td>boo</td>
+    </tr>
+    </tbody>
+</table>

test/specs/new/table_following_text.md

@@ -0,0 +1,15 @@
+---
+gfm: true
+---
+hello world
+| abc | def |
+| --- | --- |
+| bar | foo |
+| baz | boo |
+
+hello world with empty line
+
+| abc | def |
+| --- | --- |
+| bar | foo |
+| baz | boo |

test/unit/Lexer-spec.js

@@ -204,6 +204,52 @@ lheading 2
       });
     });
 
+    it('table after para', () => {
+      expectTokens({
+        md: `
+paragraph 1
+| a | b |
+|---|---|
+| 1 | 2 |
+`,
+        tokens: [
+          {
+            type: 'paragraph',
+            raw: 'paragraph 1',
+            text: 'paragraph 1',
+            tokens: [{ type: 'text', raw: 'paragraph 1', text: 'paragraph 1' }]
+          },
+          {
+            type: 'table',
+            align: [null, null],
+            raw: '| a | b |\n|---|---|\n| 1 | 2 |\n',
+            header: [
+              {
+                text: 'a',
+                tokens: [{ type: 'text', raw: 'a', text: 'a' }]
+              },
+              {
+                text: 'b',
+                tokens: [{ type: 'text', raw: 'b', text: 'b' }]
+              }
+            ],
+            rows: [
+              [
+                {
+                  text: '1',
+                  tokens: [{ type: 'text', raw: '1', text: '1' }]
+                },
+                {
+                  text: '2',
+                  tokens: [{ type: 'text', raw: '2', text: '2' }]
+                }
+              ]
+            ]
+          }
+        ]
+      });
+    });
+
     it('align table', () => {
       expectTokens({
         md: `