From 66c5a5ad765973056b61480fe9a4cba406ebda4d Mon Sep 17 00:00:00 2001 From: Rohan Challa Date: Thu, 21 Nov 2019 11:26:10 -0500 Subject: [PATCH] internal/lsp: add control flow highlighting inside for loops When the cursor is on a "for" statement or on any branch statement inside the for loop. It will highlight the control flow inside the for loop. Updates #34496 Change-Id: Idef14e3c89bc161d305d4a49fd784095a93bbc03 Reviewed-on: https://go-review.googlesource.com/c/tools/+/208337 Run-TryBot: Rebecca Stambler TryBot-Result: Gobot Gobot Reviewed-by: Rebecca Stambler --- internal/lsp/source/highlight.go | 104 ++++++++++++++---- .../lsp/testdata/highlights/highlights.go | 32 ++++++ internal/lsp/testdata/summary.txt.golden | 2 +- 3 files changed, 116 insertions(+), 22 deletions(-) diff --git a/internal/lsp/source/highlight.go b/internal/lsp/source/highlight.go index 560956065c..fef7e94b88 100644 --- a/internal/lsp/source/highlight.go +++ b/internal/lsp/source/highlight.go @@ -10,6 +10,7 @@ import ( "golang.org/x/tools/go/ast/astutil" "golang.org/x/tools/internal/lsp/protocol" + "golang.org/x/tools/internal/telemetry/log" "golang.org/x/tools/internal/telemetry/trace" errors "golang.org/x/xerrors" ) @@ -55,33 +56,94 @@ func Highlight(ctx context.Context, snapshot Snapshot, f File, pos protocol.Posi if len(path) == 0 { return nil, errors.Errorf("no enclosing position found for %v:%v", int(pos.Line), int(pos.Character)) } - result := []protocol.Range{} - id, ok := path[0].(*ast.Ident) - if !ok { - // If the cursor is not within an identifier, return empty results. - return result, nil - } - idObj := pkg.GetTypesInfo().ObjectOf(id) - ast.Inspect(path[len(path)-1], func(node ast.Node) bool { - n, ok := node.(*ast.Ident) - if !ok { - return true + switch path[0].(type) { + case *ast.Ident: + return highlightIdentifiers(ctx, snapshot, m, path, pkg) + case *ast.BranchStmt, *ast.ForStmt, *ast.RangeStmt: + return highlightControlFlow(ctx, snapshot, m, path) + } + + // If the cursor is in an unidentified area, return empty results. + return nil, nil +} + +func highlightControlFlow(ctx context.Context, snapshot Snapshot, m *protocol.ColumnMapper, path []ast.Node) ([]protocol.Range, error) { + // Reverse walk the path till we get to the for loop. + var loop ast.Node +Outer: + for _, n := range path { + switch n.(type) { + case *ast.ForStmt, *ast.RangeStmt: + loop = n + break Outer } - if n.Name != id.Name { - return true + } + if loop == nil { + // Cursor is not in a for loop. + return nil, nil + } + + var result []protocol.Range + + // Add the for statement. + forStmt, err := posToRange(ctx, snapshot.View(), m, loop.Pos(), loop.Pos()+3) + if err != nil { + return nil, err + } + rng, err := forStmt.Range() + if err != nil { + return nil, err + } + result = append(result, rng) + + ast.Inspect(loop, func(n ast.Node) bool { + // Don't traverse any other for loops. + switch n.(type) { + case *ast.ForStmt, *ast.RangeStmt: + return loop == n } - if n.Obj != id.Obj { - return true - } - nodeObj := pkg.GetTypesInfo().ObjectOf(n) - if nodeObj != idObj { - return false - } - if rng, err := nodeToProtocolRange(ctx, snapshot.View(), m, n); err == nil { + + if n, ok := n.(*ast.BranchStmt); ok { + // Add all branch statements in same scope as the identified one. + rng, err := nodeToProtocolRange(ctx, snapshot.View(), m, n) + if err != nil { + log.Error(ctx, "Error getting range for node", err) + return false + } result = append(result, rng) } return true }) return result, nil } + +func highlightIdentifiers(ctx context.Context, snapshot Snapshot, m *protocol.ColumnMapper, path []ast.Node, pkg Package) ([]protocol.Range, error) { + var result []protocol.Range + id, ok := path[0].(*ast.Ident) + if !ok { + return nil, errors.Errorf("highlightIdentifiers called with an ast.Node of type %T", id) + } + + idObj := pkg.GetTypesInfo().ObjectOf(id) + ast.Inspect(path[len(path)-1], func(node ast.Node) bool { + n, ok := node.(*ast.Ident) + if !ok { + return true + } + if n.Name != id.Name || n.Obj != id.Obj { + return false + } + if nObj := pkg.GetTypesInfo().ObjectOf(n); nObj != idObj { + return false + } + + if rng, err := nodeToProtocolRange(ctx, snapshot.View(), m, n); err == nil { + result = append(result, rng) + } else { + log.Error(ctx, "Error getting range for node", err) + } + return false + }) + return result, nil +} diff --git a/internal/lsp/testdata/highlights/highlights.go b/internal/lsp/testdata/highlights/highlights.go index dccd27e367..fdcc174ddd 100644 --- a/internal/lsp/testdata/highlights/highlights.go +++ b/internal/lsp/testdata/highlights/highlights.go @@ -36,3 +36,35 @@ func toProtocolHighlight(rngs []protocol.Range) []protocol.DocumentHighlight { / } return result } + +func testForLoops() { + for i := 0; i < 10; i++ { //@mark(forDecl1, "for"),highlight(forDecl1, forDecl1, brk1, cont1) + if i > 8 { + break //@mark(brk1, "break"),highlight(brk1, forDecl1, brk1, cont1) + } + if i < 2 { + for j := 1; j < 10; j++ { //@mark(forDecl2, "for"),highlight(forDecl2, forDecl2, cont2) + if j < 3 { + for k := 1; k < 10; k++ { //@mark(forDecl3, "for"),highlight(forDecl3, forDecl3, cont3) + if k < 3 { + continue //@mark(cont3, "continue"),highlight(cont3, forDecl3, cont3) + } + } + continue //@mark(cont2, "continue"),highlight(cont2, forDecl2, cont2) + } + } + continue //@mark(cont1, "continue"),highlight(cont1, forDecl1, brk1, cont1) + } + } + + arr := []int{} + + for i := range arr { //@mark(forDecl4, "for"),highlight(forDecl4, forDecl4, brk4, cont4) + if i > 8 { + break //@mark(brk4, "break"),highlight(brk4, forDecl4, brk4, cont4) + } + if i < 4 { + continue //@mark(cont4, "continue"),highlight(cont4, forDecl4, brk4, cont4) + } + } +} diff --git a/internal/lsp/testdata/summary.txt.golden b/internal/lsp/testdata/summary.txt.golden index 04e67c1d5a..743cd38823 100644 --- a/internal/lsp/testdata/summary.txt.golden +++ b/internal/lsp/testdata/summary.txt.golden @@ -13,7 +13,7 @@ ImportCount = 7 SuggestedFixCount = 1 DefinitionsCount = 37 TypeDefinitionsCount = 2 -HighlightsCount = 12 +HighlightsCount = 22 ReferencesCount = 7 RenamesCount = 22 PrepareRenamesCount = 8