feat(yaml): add support for YAML block folded scalars

Closes #249

apidom/packages/apidom-ast/src/nodes/yaml/YamlScalar/formats.ts

@@ -2,12 +2,9 @@ import {
   tail,
   compose,
   pathOr,
-  __,
   map,
   concat,
   transduce,
-  ifElse,
-  always,
   prop,
   pipe,
   trim,
@@ -86,7 +83,9 @@ const preventNlCollapseToSpace = (val: string) => val.replace(/\\\n\s*/g, '');
 
 // collapse newlines into spaces
 const collapseNlToSpace = (val: string) =>
-  val.replace(/\n([^\n]+)/g, (match: string, p1: string) => ` ${p1.trimLeft()}`);
+  val
+    .replace(/(?<![\n]+)\n([^\n]+)/g, (match: string, p1: string) => ` ${p1.trimLeft()}`)
+    .replace(/[\n]{2}/g, '\n');
 
 const removeQuotes = curry((quoteType, val) =>
   val.replace(new RegExp(`^${quoteType}`), '').replace(new RegExp(`${quoteType}$`), ''),
@@ -149,9 +148,9 @@ export const formatBlockLiteral = (scalarNode: any): string => {
   const lines = tail(scalarNode.text.split('\n')); // first line only contains indicators
   const transducer = compose(map(trimCharsStart(indentation)), map(concatRight('\n')));
   // @ts-ignore
-  const formatted: string = transduce(transducer, concat, '', lines);
+  const deindented: string = transduce(transducer, concat, '', lines);
 
-  return chomp(chompingIndicator, formatted);
+  return chomp(chompingIndicator, deindented);
 };
 
 /**
@@ -162,14 +161,10 @@ export const formatBlockFolded = (scalarNode: any): string => {
   const indentation = getIndentation(scalarNode);
   const chompingIndicator = getChompingIndicator(scalarNode);
   const lines = tail(scalarNode.text.split('\n')); // first line only contains indicators
+  const transducer = compose(map(trimCharsStart(indentation)), map(concatRight('\n')));
   // @ts-ignore
-  const transducer = compose(
-    map(trimCharsStart(indentation)),
-    // @ts-ignore
-    map(ifElse(isEmptyString, always('\n'), concat(__, ' '))),
-  );
-  // @ts-ignore
-  const formatted: string = transduce(transducer, concat, '', lines);
+  const deindented: string = transduce(transducer, concat, '', lines);
+  const collapsed = collapseNlToSpace(deindented);
 
-  return chomp(chompingIndicator, formatted);
+  return chomp(chompingIndicator, collapsed);
 };

apidom/packages/apidom-ast/src/nodes/yaml/YamlScalar/index.ts

@@ -7,6 +7,7 @@ import {
   formatFlowSingleQuoted,
   formatFlowDoubleQuoted,
   formatBlockLiteral,
+  formatBlockFolded,
 } from './formats';
 
 interface YamlScalar extends YamlNode {
@@ -45,6 +46,10 @@ const YamlScalar: stampit.Stamp<YamlScalar> = stampit(YamlNode, {
         // @ts-ignore
         return formatBlockLiteral(this);
       }
+      if (this.style === YamlStyle.Folded) {
+        // @ts-ignore
+        return formatBlockFolded(this);
+      }
 
       // @ts-ignore
       return this.text;

apidom/packages/apidom-ast/test/nodes/yaml/YamlScalar/formats/fixtures/folded-clip-expected.yaml

@@ -0,0 +1,2 @@
+Several lines of text, with some "quotes" of various 'types', and also a blank line:
+plus another line at the end.

apidom/packages/apidom-ast/test/nodes/yaml/YamlScalar/formats/fixtures/folded-clip.yaml

@@ -0,0 +1,7 @@
+>
+  Several lines of text,
+  with some "quotes" of various 'types',
+  and also a blank line:
+
+  plus another line at the end.
+

apidom/packages/apidom-ast/test/nodes/yaml/YamlScalar/formats/fixtures/folded-indentation-indicator-expected.yaml

@@ -0,0 +1,2 @@
+Several lines of text, with some "quotes" of various 'types', and also a blank line:
+plus another line at the end.

apidom/packages/apidom-ast/test/nodes/yaml/YamlScalar/formats/fixtures/folded-indentation-indicator.yaml

@@ -0,0 +1,7 @@
+>2
+  Several lines of text,
+  with some "quotes" of various 'types',
+  and also a blank line:
+
+  plus another line at the end.
+

apidom/packages/apidom-ast/test/nodes/yaml/YamlScalar/formats/fixtures/folded-keep-expected.yaml

@@ -0,0 +1,3 @@
+Several lines of text, with some "quotes" of various 'types', and also a blank line:
+plus another line at the end.
+

apidom/packages/apidom-ast/test/nodes/yaml/YamlScalar/formats/fixtures/folded-keep.yaml

@@ -0,0 +1,7 @@
+>+
+  Several lines of text,
+  with some "quotes" of various 'types',
+  and also a blank line:
+
+  plus another line at the end.
+

apidom/packages/apidom-ast/test/nodes/yaml/YamlScalar/formats/fixtures/folded-strip-expected.yaml

@@ -0,0 +1,2 @@
+Several lines of text, with some "quotes" of various 'types', and also a blank line:
+plus another line at the end.

apidom/packages/apidom-ast/test/nodes/yaml/YamlScalar/formats/fixtures/folded-strip.yaml

@@ -0,0 +1,7 @@
+>-
+  Several lines of text,
+  with some "quotes" of various 'types',
+  and also a blank line:
+
+  plus another line at the end.
+

apidom/packages/apidom-ast/test/nodes/yaml/YamlScalar/formats/index.ts

@@ -23,11 +23,35 @@ const literalStripExpectedPath = path.join(__dirname, 'fixtures', 'literal-strip
 const literalClipPath = path.join(__dirname, 'fixtures', 'literal-clip.yaml');
 const literalClipExpectedPath = path.join(__dirname, 'fixtures', 'literal-clip-expected.yaml');
 
-const literalIndentationIndicatorPath = path.join(__dirname, 'fixtures', 'literal-clip.yaml');
+const literalIndentationIndicatorPath = path.join(
+  __dirname,
+  'fixtures',
+  'literal-indentation-indicator.yaml',
+);
 const literalIndentationIndicatorExpectedPath = path.join(
   __dirname,
   'fixtures',
-  'literal-clip-expected.yaml',
+  'literal-indentation-indicator-expected.yaml',
+);
+
+const foldedKeepPath = path.join(__dirname, 'fixtures', 'folded-keep.yaml');
+const foldedKeepExpectedPath = path.join(__dirname, 'fixtures', 'folded-keep-expected.yaml');
+
+const foldedStripPath = path.join(__dirname, 'fixtures', 'folded-strip.yaml');
+const foldedStripExpectedPath = path.join(__dirname, 'fixtures', 'folded-strip-expected.yaml');
+
+const foldedClipPath = path.join(__dirname, 'fixtures', 'folded-clip.yaml');
+const foldedClipExpectedPath = path.join(__dirname, 'fixtures', 'folded-clip-expected.yaml');
+
+const foldedIndentationIndicatorPath = path.join(
+  __dirname,
+  'fixtures',
+  'folded-indentation-indicator.yaml',
+);
+const foldedIndentationIndicatorExpectedPath = path.join(
+  __dirname,
+  'fixtures',
+  'folded-indentation-indicator-expected.yaml',
 );
 
 describe('nodes', function () {
@@ -120,6 +144,52 @@ describe('nodes', function () {
             assert.strictEqual(scalar.content, expected);
           });
         });
+
+        context('formatBlockFolded', function () {
+          specify('should format folded + keep', function () {
+            const text = fs.readFileSync(foldedKeepPath).toString();
+            const scalar = YamlScalar({
+              style: YamlStyle.Folded,
+              styleGroup: YamlStyleGroup.Block,
+              text,
+            });
+            const expected = fs.readFileSync(foldedKeepExpectedPath).toString();
+            assert.strictEqual(scalar.content, expected);
+          });
+
+          specify('should format folded + strip', function () {
+            const text = fs.readFileSync(foldedStripPath).toString();
+            const scalar = YamlScalar({
+              style: YamlStyle.Folded,
+              styleGroup: YamlStyleGroup.Block,
+              text,
+            });
+            const expected = fs.readFileSync(foldedStripExpectedPath).toString().trimRight();
+            assert.strictEqual(scalar.content, expected);
+          });
+
+          specify('should format folded + clip', function () {
+            const text = fs.readFileSync(foldedClipPath).toString();
+            const scalar = YamlScalar({
+              style: YamlStyle.Folded,
+              styleGroup: YamlStyleGroup.Block,
+              text,
+            });
+            const expected = fs.readFileSync(foldedClipExpectedPath).toString();
+            assert.strictEqual(scalar.content, expected);
+          });
+
+          specify('should format folded + clip + indentation indicator', function () {
+            const text = fs.readFileSync(foldedIndentationIndicatorPath).toString();
+            const scalar = YamlScalar({
+              style: YamlStyle.Folded,
+              styleGroup: YamlStyleGroup.Block,
+              text,
+            });
+            const expected = fs.readFileSync(foldedIndentationIndicatorExpectedPath).toString();
+            assert.strictEqual(scalar.content, expected);
+          });
+        });
       });
     });
   });