IJPL-250551 [markdown] don't ignore "Keep line breaks inside text blocks" option

GitOrigin-RevId: 9de834d5dce52ea3210947bbc05cad428cf4d71a

plugins/markdown/core/src/org/intellij/plugins/markdown/lang/formatter/MarkdownSpacingBuilder.kt

@@ -83,7 +83,7 @@ internal object MarkdownSpacingBuilder {
       .apply {
         val spaces = if (markdown.FORCE_ONE_SPACE_BETWEEN_WORDS) 1 else Integer.MAX_VALUE
         between(MarkdownTokenTypes.TEXT, MarkdownTokenTypes.TEXT)
-          .spacing(1, spaces, 0, markdown.KEEP_LINE_BREAKS_INSIDE_TEXT_BLOCKS && !markdown.WRAP_TEXT_IF_LONG, 0)
+          .spacing(1, spaces, 0, markdown.KEEP_LINE_BREAKS_INSIDE_TEXT_BLOCKS, 0)
         between(MarkdownTokenTypes.TEXT, MarkdownElementTypes.STRONG).spacing(1, spaces, 0, false, 0)
         between(MarkdownTokenTypes.TEXT, MarkdownElementTypes.EMPH).spacing(1, spaces, 0, false, 0)
         between(MarkdownTokenTypes.TEXT, MarkdownElementTypes.STRIKETHROUGH).spacing(1, spaces, 0, false, 0)

plugins/markdown/test/data/formatter/keep_line_breaks_inside_text_block_after.md

@@ -0,0 +1,2 @@
+Lorem ipsum dolor sit amet, consectetur adipiscing elit. Curabitur non dignissim tellus, sed feugiat ante.
+In bibendum orci quis ultricies lobortis. Curabitur ac sapien efficitur quam ullamcorper varius.

plugins/markdown/test/data/formatter/keep_line_breaks_inside_text_block_before.md

@@ -0,0 +1,2 @@
+Lorem ipsum dolor sit amet, consectetur adipiscing elit. Curabitur non dignissim tellus, sed feugiat ante.
+In bibendum orci quis ultricies lobortis. Curabitur ac sapien efficitur quam ullamcorper varius.

plugins/markdown/test/data/formatter/reflow_no_extra_new_lines_keep_line_breaks_margin_80_before.md

@@ -1,3 +0,0 @@
-- **Logic:** Iterate through slides. For each slide, identify the Title shape and the content shapes
-  (Body). Process paragraphs within these shapes to maintain the hierarchical structure
-  (indentation).

plugins/markdown/test/data/formatter/text_block_reflow_after_decreasing_margin_before.md

@@ -0,0 +1 @@
+- **Logic:** Iterate through slides. For each slide, identify the Title shape and the content shapes (Body). Process paragraphs within these shapes to maintain the hierarchical structure (indentation).

plugins/markdown/test/src/org/intellij/plugins/markdown/formatter/MarkdownFormatterTest.kt

@@ -59,11 +59,37 @@ class MarkdownFormatterTest: LightPlatformCodeInsightTestCase() {
 
   fun `test reflow no extra new lines`() = doTest(rightMargin = 80)
 
-  fun `test reflow no extra new lines keep line breaks margin 80`() = doTest(rightMargin = 80, keepLineBreaks = true)
+  fun `test reflow no extra new lines keep line breaks margin 60`() = doTest(rightMargin = 60)
 
-  fun `test reflow no extra new lines keep line breaks margin 60`() = doTest(rightMargin = 60, keepLineBreaks = true)
+  fun `test reflow no extra new lines keep line breaks margin 40`() = doTest(rightMargin = 40)
 
-  fun `test reflow no extra new lines keep line breaks margin 40`() = doTest(rightMargin = 40, keepLineBreaks = true)
+  fun `test keep line breaks inside text block`() = doTest(rightMargin = 120, keepLineBreaks = true)
+
+  // IJPL-241496: a single long line wrapped at 100 and then reformatted at 80 must reflow cleanly,
+  // not accumulate extra line breaks, when "keep line breaks inside text blocks" is disabled.
+  fun `test text block reflow after decreasing margin`() {
+    runWithTemporaryStyleSettings(project) { settings ->
+      settings.apply {
+        WRAP_WHEN_TYPING_REACHES_RIGHT_MARGIN = true
+        getCustomSettings(MarkdownCustomCodeStyleSettings::class.java).apply {
+          FORMAT_TABLES = false
+          WRAP_TEXT_IF_LONG = true
+          KEEP_LINE_BREAKS_INSIDE_TEXT_BLOCKS = false
+        }
+      }
+      val common = settings.getCommonSettings(MarkdownLanguage.INSTANCE)
+      val after = getTestName(true) + "_after.md"
+      configureByFile(getTestName(true) + "_before.md")
+      common.RIGHT_MARGIN = 100
+      performReformatting(project, file)
+      common.RIGHT_MARGIN = 80
+      performReformatting(project, file)
+      checkResultByFile(after)
+      // reformatting again at 80 must stay stable
+      performReformatting(project, file)
+      checkResultByFile(after)
+    }
+  }
 
   fun `test emphasis`() = doTest()