dashboard/app: export info about uncovered blocks as well

Currently it's only possible to understand total number of uncovered
blocks in a function (implicitly defined by Instrumented field).
This does not allow to render coverage data, nor do detailed analysis
on line level. Export detailed info about both covered and uncovered blocks.
This allows to e.g. calculate coverage percent for kernel interfaces.

4 files changed, 42 insertions, 46 deletions

diff --git a/dashboard/app/public_json_api.go b/dashboard/app/public_json_api.go
index aa99b41a8..90e2fe8d6 100644
--- a/dashboard/app/public_json_api.go
+++ b/dashboard/app/public_json_api.go
@@ -232,42 +232,29 @@ func writeFileCoverage(ctx context.Context, w io.Writer, repo string, ff *covera
 }
 
 func genFuncsCov(fc *coveragedb.FileCoverageWithLineInfo, ff *coveragedb.FunctionFinder,
-) ([]*cover.FunctionCoverage, error) {
-	nameToLines := map[string][]int{}
-	funcInstrumented := map[string]int{}
+) ([]*cover.FuncCoverage, error) {
+	nameToLines := map[string][]*cover.Block{}
 	for i, hitCount := range fc.HitCounts {
 		lineNum := int(fc.LinesInstrumented[i])
 		funcName, err := ff.FileLineToFuncName(fc.Filepath, lineNum)
 		if err != nil {
 			return nil, fmt.Errorf("ff.FileLineToFuncName: %w", err)
 		}
-		funcInstrumented[funcName]++
-		if hitCount == 0 {
-			continue
-		}
-		nameToLines[funcName] = append(nameToLines[funcName], lineNum)
-	}
-
-	var res []*cover.FunctionCoverage
-	for funcName, lines := range nameToLines {
-		res = append(res, &cover.FunctionCoverage{
-			FuncName:     funcName,
-			Instrumented: funcInstrumented[funcName],
-			Blocks:       linesToBlocks(lines),
-		})
-	}
-	return res, nil
-}
-
-func linesToBlocks(lines []int) []*cover.CoveredBlock {
-	var res []*cover.CoveredBlock
-	for _, lineNum := range lines {
-		res = append(res, &cover.CoveredBlock{
+		nameToLines[funcName] = append(nameToLines[funcName], &cover.Block{
+			HitCount: int(hitCount),
 			FromLine: lineNum,
 			FromCol:  0,
 			ToLine:   lineNum,
 			ToCol:    -1,
 		})
 	}
-	return res
+
+	var res []*cover.FuncCoverage
+	for funcName, blocks := range nameToLines {
+		res = append(res, &cover.FuncCoverage{
+			FuncName: funcName,
+			Blocks:   blocks,
+		})
+	}
+	return res, nil
 }
diff --git a/dashboard/app/public_json_api_test.go b/dashboard/app/public_json_api_test.go
index de51bd3b7..f0aee9f79 100644
--- a/dashboard/app/public_json_api_test.go
+++ b/dashboard/app/public_json_api_test.go
@@ -264,7 +264,7 @@ func TestWriteExtAPICoverageFor(t *testing.T) {
 			{
 				FilePath: "/file",
 				FuncName: "func_name",
-				Lines:    []int64{1, 2, 3},
+				Lines:    []int64{1, 2, 3, 4},
 			},
 		},
 		[]*coveragedb.FileCoverageWithLineInfo{
@@ -273,8 +273,8 @@ func TestWriteExtAPICoverageFor(t *testing.T) {
 					Filepath: "/file",
 					Commit:   "test-commit",
 				},
-				LinesInstrumented: []int64{1, 2, 3},
-				HitCounts:         []int64{10, 20, 30},
+				LinesInstrumented: []int64{1, 2, 3, 4},
+				HitCounts:         []int64{10, 20, 30, 0},
 			},
 		},
 	))
@@ -289,25 +289,33 @@ func TestWriteExtAPICoverageFor(t *testing.T) {
 	"functions": [
 		{
 			"func_name": "func_name",
-			"total_blocks": 3,
-			"covered_blocks": [
+			"blocks": [
 				{
+					"hit_count": 10,
 					"from_line": 1,
 					"from_column": 0,
 					"to_line": 1,
 					"to_column": -1
 				},
 				{
+					"hit_count": 20,
 					"from_line": 2,
 					"from_column": 0,
 					"to_line": 2,
 					"to_column": -1
 				},
 				{
+					"hit_count": 30,
 					"from_line": 3,
 					"from_column": 0,
 					"to_line": 3,
 					"to_column": -1
+				},
+				{
+					"from_line": 4,
+					"from_column": 0,
+					"to_line": 4,
+					"to_column": -1
 				}
 			]
 		}
diff --git a/pkg/cover/html.go b/pkg/cover/html.go
index c7bd945b6..1b2d4d024 100644
--- a/pkg/cover/html.go
+++ b/pkg/cover/html.go
@@ -264,19 +264,19 @@ type ProgramCoverage struct {
 }
 
 type FileCoverage struct {
-	Repo      string              `json:"repo,omitempty"`
-	Commit    string              `json:"commit,omitempty"`
-	FilePath  string              `json:"file_path"`
-	Functions []*FunctionCoverage `json:"functions"`
+	Repo      string          `json:"repo,omitempty"`
+	Commit    string          `json:"commit,omitempty"`
+	FilePath  string          `json:"file_path"`
+	Functions []*FuncCoverage `json:"functions"`
 }
 
-type FunctionCoverage struct {
-	FuncName     string          `json:"func_name"`
-	Instrumented int             `json:"total_blocks,omitempty"`
-	Blocks       []*CoveredBlock `json:"covered_blocks"`
+type FuncCoverage struct {
+	FuncName string   `json:"func_name"`
+	Blocks   []*Block `json:"blocks"`
 }
 
-type CoveredBlock struct {
+type Block struct {
+	HitCount int `json:"hit_count,omitempty"`
 	FromLine int `json:"from_line"`
 	FromCol  int `json:"from_column"`
 	ToLine   int `json:"to_line"`
@@ -312,22 +312,23 @@ func (rg *ReportGenerator) DoCoverPrograms(w io.Writer, params HandlerParams) er
 
 		var progCoverage []*FileCoverage
 		for filePath, functions := range fileFuncFrames {
-			var expFuncs []*FunctionCoverage
+			var expFuncs []*FuncCoverage
 			for funcName, frames := range functions {
-				var expCoveredBlocks []*CoveredBlock
+				var expCoveredBlocks []*Block
 				for _, frame := range frames {
 					endCol := frame.EndCol
 					if endCol == backend.LineEnd {
 						endCol = -1
 					}
-					expCoveredBlocks = append(expCoveredBlocks, &CoveredBlock{
+					expCoveredBlocks = append(expCoveredBlocks, &Block{
+						HitCount: 1,
 						FromCol:  frame.StartCol,
 						FromLine: frame.StartLine,
 						ToCol:    endCol,
 						ToLine:   frame.EndLine,
 					})
 				}
-				expFuncs = append(expFuncs, &FunctionCoverage{
+				expFuncs = append(expFuncs, &FuncCoverage{
 					FuncName: funcName,
 					Blocks:   expCoveredBlocks,
 				})
diff --git a/pkg/cover/report_test.go b/pkg/cover/report_test.go
index 002ff1958..96b634cc6 100644
--- a/pkg/cover/report_test.go
+++ b/pkg/cover/report_test.go
@@ -424,7 +424,6 @@ func checkCSVReport(t *testing.T, CSVReport []byte) {
 	}
 }
 
-// nolint:lll
 func checkJSONLReport(t *testing.T, gotBytes, wantBytes []byte) {
 	compacted := new(bytes.Buffer)
 	if err := json.Compact(compacted, wantBytes); err != nil {
@@ -446,8 +445,9 @@ var sampleJSONLlProgs = []byte(`{
 			"functions": [
 				{
 					"func_name": "main",
-					"covered_blocks": [
+					"blocks": [
 						{
+							"hit_count": 1,
 							"from_line": 1,
 							"from_column": 0,
 							"to_line": 1,