internal/lsp: add tests for nested folding ranges

FoldingRanges may be nested. Test nested folding ranges by separating
out the folding ranges by nested level and checking each level.

Change-Id: I12c72daa3e6c6b9d4959209b3a41b27e2b59866f
Reviewed-on: https://go-review.googlesource.com/c/tools/+/192398
Run-TryBot: Suzy Mueller <suzmue@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rebecca Stambler <rstambler@golang.org>

internal/lsp/lsp_test.go

@@ -290,17 +290,21 @@ func (r *runner) FoldingRange(t *testing.T, data tests.FoldingRanges) {
 		}
 
 		// Fold all ranges.
-		got, err := foldRanges(m, string(m.Content), ranges)
-		if err != nil {
-			t.Error(err)
-			continue
-		}
-		want := string(r.data.Golden("foldingRange", spn.URI().Filename(), func() ([]byte, error) {
-			return []byte(got), nil
-		}))
+		nonOverlapping := nonOverlappingRanges(ranges)
+		for i, rngs := range nonOverlapping {
+			got, err := foldRanges(m, string(m.Content), rngs)
+			if err != nil {
+				t.Error(err)
+				continue
+			}
+			tag := fmt.Sprintf("foldingRange-%d", i)
+			want := string(r.data.Golden(tag, spn.URI().Filename(), func() ([]byte, error) {
+				return []byte(got), nil
+			}))
 
-		if want != got {
-			t.Errorf("foldingRanges failed for %s, expected:\n%v\ngot:\n%v", filename, want, got)
+			if want != got {
+				t.Errorf("%s: foldingRanges failed for %s, expected:\n%v\ngot:\n%v", tag, filename, want, got)
+			}
 		}
 
 		// Filter by kind.
@@ -313,17 +317,21 @@ func (r *runner) FoldingRange(t *testing.T, data tests.FoldingRanges) {
 				}
 			}
 
-			got, err := foldRanges(m, string(m.Content), kindOnly)
-			if err != nil {
-				t.Error(err)
-				continue
-			}
-			want := string(r.data.Golden("foldingRange-"+string(kind), spn.URI().Filename(), func() ([]byte, error) {
-				return []byte(got), nil
-			}))
+			nonOverlapping := nonOverlappingRanges(kindOnly)
+			for i, rngs := range nonOverlapping {
+				got, err := foldRanges(m, string(m.Content), rngs)
+				if err != nil {
+					t.Error(err)
+					continue
+				}
+				tag := fmt.Sprintf("foldingRange-%s-%d", kind, i)
+				want := string(r.data.Golden(tag, spn.URI().Filename(), func() ([]byte, error) {
+					return []byte(got), nil
+				}))
 
-			if want != got {
-				t.Errorf("foldingRanges-%s failed for %s, expected:\n%v\ngot:\n%v", string(kind), filename, want, got)
+				if want != got {
+					t.Errorf("%s: foldingRanges failed for %s, expected:\n%v\ngot:\n%v", tag, filename, want, got)
+				}
 			}
 
 		}
@@ -331,9 +339,37 @@ func (r *runner) FoldingRange(t *testing.T, data tests.FoldingRanges) {
 	}
 }
 
+func nonOverlappingRanges(ranges []protocol.FoldingRange) (res [][]protocol.FoldingRange) {
+	for _, fRng := range ranges {
+		setNum := len(res)
+		for i := 0; i < len(res); i++ {
+			canInsert := true
+			for _, rng := range res[i] {
+				if conflict(rng, fRng) {
+					canInsert = false
+					break
+				}
+			}
+			if canInsert {
+				setNum = i
+				break
+			}
+		}
+		if setNum == len(res) {
+			res = append(res, []protocol.FoldingRange{})
+		}
+		res[setNum] = append(res[setNum], fRng)
+	}
+	return res
+}
+
+func conflict(a, b protocol.FoldingRange) bool {
+	// a start position is <= b start positions
+	return (a.StartLine < b.StartLine || (a.StartLine == b.StartLine && a.StartCharacter <= b.StartCharacter)) &&
+		(a.EndLine > b.StartLine || (a.EndLine == b.StartLine && a.EndCharacter > b.StartCharacter))
+}
+
 func foldRanges(m *protocol.ColumnMapper, contents string, ranges []protocol.FoldingRange) (string, error) {
-	// TODO(suzmue): Allow folding ranges to intersect for these tests, do a folding by level,
-	// or per individual fold.
 	foldedText := "<>"
 	res := contents
 	// Apply the edits from the end of the file forward

internal/lsp/source/source_test.go

@@ -288,18 +288,23 @@ func (r *runner) FoldingRange(t *testing.T, data tests.FoldingRanges) {
 			t.Error(err)
 			continue
 		}
-		// Fold all ranges.
-		got, err := foldRanges(string(data), ranges)
-		if err != nil {
-			t.Error(err)
-			continue
-		}
-		want := string(r.data.Golden("foldingRange", spn.URI().Filename(), func() ([]byte, error) {
-			return []byte(got), nil
-		}))
 
-		if want != got {
-			t.Errorf("foldingRanges failed for %s, expected:\n%v\ngot:\n%v", filename, want, got)
+		// Fold all ranges.
+		nonOverlapping := nonOverlappingRanges(ranges)
+		for i, rngs := range nonOverlapping {
+			got, err := foldRanges(string(data), rngs)
+			if err != nil {
+				t.Error(err)
+				continue
+			}
+			tag := fmt.Sprintf("foldingRange-%d", i)
+			want := string(r.data.Golden(tag, spn.URI().Filename(), func() ([]byte, error) {
+				return []byte(got), nil
+			}))
+
+			if want != got {
+				t.Errorf("%s: foldingRanges failed for %s, expected:\n%v\ngot:\n%v", tag, filename, want, got)
+			}
 		}
 
 		// Filter by kind.
@@ -312,17 +317,21 @@ func (r *runner) FoldingRange(t *testing.T, data tests.FoldingRanges) {
 				}
 			}
 
-			got, err := foldRanges(string(data), kindOnly)
-			if err != nil {
-				t.Error(err)
-				continue
-			}
-			want := string(r.data.Golden("foldingRange-"+string(kind), spn.URI().Filename(), func() ([]byte, error) {
-				return []byte(got), nil
-			}))
+			nonOverlapping := nonOverlappingRanges(kindOnly)
+			for i, rngs := range nonOverlapping {
+				got, err := foldRanges(string(data), rngs)
+				if err != nil {
+					t.Error(err)
+					continue
+				}
+				tag := fmt.Sprintf("foldingRange-%s-%d", kind, i)
+				want := string(r.data.Golden(tag, spn.URI().Filename(), func() ([]byte, error) {
+					return []byte(got), nil
+				}))
 
-			if want != got {
-				t.Errorf("foldingRanges-%s failed for %s, expected:\n%v\ngot:\n%v", string(kind), filename, want, got)
+				if want != got {
+					t.Errorf("%s: failed for %s, expected:\n%v\ngot:\n%v", tag, filename, want, got)
+				}
 			}
 
 		}
@@ -330,8 +339,36 @@ func (r *runner) FoldingRange(t *testing.T, data tests.FoldingRanges) {
 	}
 }
 
+func nonOverlappingRanges(ranges []source.FoldingRangeInfo) (res [][]source.FoldingRangeInfo) {
+	for _, fRng := range ranges {
+		setNum := len(res)
+		for i := 0; i < len(res); i++ {
+			canInsert := true
+			for _, rng := range res[i] {
+				if conflict(rng, fRng) {
+					canInsert = false
+					break
+				}
+			}
+			if canInsert {
+				setNum = i
+				break
+			}
+		}
+		if setNum == len(res) {
+			res = append(res, []source.FoldingRangeInfo{})
+		}
+		res[setNum] = append(res[setNum], fRng)
+	}
+	return res
+}
+
+func conflict(a, b source.FoldingRangeInfo) bool {
+	// a start position is <= b start positions
+	return a.Range.Start <= b.Range.Start && a.Range.End > b.Range.Start
+}
+
 func foldRanges(contents string, ranges []source.FoldingRangeInfo) (string, error) {
-	// TODO(suzmue): Allow folding ranges to intersect for these tests.
 	foldedText := "<>"
 	res := contents
 	// Apply the folds from the end of the file forward

internal/lsp/testdata/folding/a.go

@@ -1,7 +1,7 @@
 package folding //@fold("package")
 
 import (
-	_ "fmt"
+	"fmt"
 	_ "log"
 )
 
@@ -10,6 +10,17 @@ import _ "os"
 // bar is a function.
 // With a multiline doc comment.
 func bar() string {
+	switch {
+	case true:
+		if true {
+			fmt.Println("true")
+		}
+	case false:
+		fmt.Println("false")
+	default:
+		fmt.Println("default")
+	}
+
 	return `
 this string
 is not indented`

internal/lsp/testdata/folding/a.go.golden

@@ -1,4 +1,4 @@
--- foldingRange --
+-- foldingRange-0 --
 package folding //@fold("package")
 
 import (<>)
@@ -8,11 +8,115 @@ import _ "os"
 // bar is a function.<>
 func bar(<>) string {<>}
 
--- foldingRange-comment --
+-- foldingRange-1 --
 package folding //@fold("package")
 
 import (
-	_ "fmt"
+	"fmt"
+	_ "log"
+)
+
+import _ "os"
+
+// bar is a function.
+// With a multiline doc comment.
+func bar() string {
+	switch {<>}
+
+	return `
+this string
+is not indented`
+
+}
+
+-- foldingRange-2 --
+package folding //@fold("package")
+
+import (
+	"fmt"
+	_ "log"
+)
+
+import _ "os"
+
+// bar is a function.
+// With a multiline doc comment.
+func bar() string {
+	switch {
+	case true:<>
+	case false:<>
+	default:<>
+	}
+
+	return `
+this string
+is not indented`
+
+}
+
+-- foldingRange-3 --
+package folding //@fold("package")
+
+import (
+	"fmt"
+	_ "log"
+)
+
+import _ "os"
+
+// bar is a function.
+// With a multiline doc comment.
+func bar() string {
+	switch {
+	case true:
+		if true {<>}
+	case false:
+		fmt.Println(<>)
+	default:
+		fmt.Println(<>)
+	}
+
+	return `
+this string
+is not indented`
+
+}
+
+-- foldingRange-4 --
+package folding //@fold("package")
+
+import (
+	"fmt"
+	_ "log"
+)
+
+import _ "os"
+
+// bar is a function.
+// With a multiline doc comment.
+func bar() string {
+	switch {
+	case true:
+		if true {
+			fmt.Println(<>)
+		}
+	case false:
+		fmt.Println("false")
+	default:
+		fmt.Println("default")
+	}
+
+	return `
+this string
+is not indented`
+
+}
+
+-- foldingRange-comment-0 --
+package folding //@fold("package")
+
+import (
+	"fmt"
 	_ "log"
 )
 
@@ -20,13 +124,24 @@ import _ "os"
 
 // bar is a function.<>
 func bar() string {
+	switch {
+	case true:
+		if true {
+			fmt.Println("true")
+		}
+	case false:
+		fmt.Println("false")
+	default:
+		fmt.Println("default")
+	}
+
 	return `
 this string
 is not indented`
 
 }
 
--- foldingRange-imports --
+-- foldingRange-imports-0 --
 package folding //@fold("package")
 
 import (<>)
@@ -36,6 +151,17 @@ import _ "os"
 // bar is a function.
 // With a multiline doc comment.
 func bar() string {
+	switch {
+	case true:
+		if true {
+			fmt.Println("true")
+		}
+	case false:
+		fmt.Println("false")
+	default:
+		fmt.Println("default")
+	}
+
 	return `
 this string
 is not indented`