Replace gometalinter -> golangci; fix lint errors

.golangci.yml

@@ -0,0 +1,9 @@
+issues:
+  exclude-rules:
+    - linters: [gosimple]
+      path: values/drop_test.go # see the note in the file
+      text: "S1005:"
+
+    # go generate introduces these
+    - path: expressions/scanner.go
+      linters: [deadcode, unused, varcheck]

CONTRIBUTING.md

@@ -21,7 +21,9 @@ Fork and clone the repo.
 Install package dependencies and development tools:
 
 * `make setup`
-* `go get -t ./...`
+
+[Install golangci-lint](https://golangci-lint.run/usage/install/#local-installation).
+On macOS: `brew install golangci-lint`
 
 ### Test and Lint
 

Makefile

@@ -24,7 +24,7 @@ imports: ## list imports
 	@go list -f '{{join .Imports "\n"}}' ./... | grep -v `go list -f '{{.ImportPath}}'` | grep '\.' | sort | uniq
 
 lint: ## lint the package
-	gometalinter ./... --tests --deadline=5m --include=gofmt --exclude expressions/scanner.go --exclude y.go --exclude '.*_string.go' --disable=gotype --disable=interfacer
+	golangci-lint run
 	@echo lint passed
 
 pre-commit: lint test ## lint and test the package
@@ -33,8 +33,6 @@ setup: ## install dependencies and development tools
 	go get golang.org/x/tools/cmd/stringer
 	go install golang.org/x/tools/cmd/goyacc
 	go get -t ./...
-	go get github.com/alecthomas/gometalinter
-	gometalinter --install
 
 test: ## test the package
 	go test ./...

engine_test.go

@@ -83,14 +83,19 @@ func BenchmarkEngine_Parse(b *testing.B) {
 	engine := NewEngine()
 	buf := new(bytes.Buffer)
 	for i := 0; i < 1000; i++ {
-		io.WriteString(buf, `if{% if true %}true{% elsif %}elsif{% else %}else{% endif %}`)
+		_, err := io.WriteString(buf, `if{% if true %}true{% elsif %}elsif{% else %}else{% endif %}`)
-		io.WriteString(buf, `loop{% for item in array %}loop{% break %}{% endfor %}`)
+		require.NoError(b, err)
-		io.WriteString(buf, `case{% case value %}{% when a %}{% when b %{% endcase %}`)
+		_, err = io.WriteString(buf, `loop{% for item in array %}loop{% break %}{% endfor %}`)
-		io.WriteString(buf, `expr{{ a and b }}{{ a add: b }}`)
+		require.NoError(b, err)
+		_, err = io.WriteString(buf, `case{% case value %}{% when a %}{% when b %{% endcase %}`)
+		require.NoError(b, err)
+		_, err = io.WriteString(buf, `expr{{ a and b }}{{ a add: b }}`)
+		require.NoError(b, err)
 	}
 	s := buf.Bytes()
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		engine.ParseTemplate(s)
+		_, err := engine.ParseTemplate(s)
+		require.NoError(b, err)
 	}
 }

expressions/expressions.y

@@ -9,7 +9,7 @@ import (
 func init() {
 	// This allows adding and removing references to fmt in the rules below,
 	// without having to comment and un-comment the import statement above.
-	_ = fmt.Sprint("")
+	_ = ""
 }
 
 %}

expressions/y.go

@@ -1,3 +1,5 @@
+// Code generated by goyacc expressions.y. DO NOT EDIT.
+
 //line expressions.y:2
 package expressions
 
@@ -13,7 +15,7 @@ import (
 func init() {
 	// This allows adding and removing references to fmt in the rules below,
 	// without having to comment and un-comment the import statement above.
-	_ = fmt.Sprint("")
+	_ = ""
 }
 
 //line expressions.y:16
@@ -84,6 +86,7 @@ var yyToknames = [...]string{
 	"'['",
 	"']'",
 }
+
 var yyStatenames = [...]string{}
 
 const yyEofCode = 1
@@ -108,7 +111,6 @@ const yyPrivate = 57344
 const yyLast = 104
 
 var yyAct = [...]int{
-
 	9, 74, 46, 41, 8, 87, 78, 23, 14, 15,
 	18, 10, 11, 25, 42, 3, 4, 5, 6, 25,
 	37, 58, 10, 11, 40, 42, 45, 50, 51, 52,
@@ -121,8 +123,8 @@ var yyAct = [...]int{
 	85, 86, 83, 19, 34, 2, 1, 73, 20, 39,
 	17, 22, 67, 63,
 }
-var yyPact = [...]int{
 
+var yyPact = [...]int{
 	7, -1000, 60, 76, 89, 71, 18, -1000, 19, 49,
 	-1000, -1000, 18, -1000, 18, 18, -6, 14, -3, -1000,
 	10, 38, 1, 39, 83, -1000, 18, 18, 18, 18,
@@ -133,29 +135,29 @@ var yyPact = [...]int{
 	-1000, -1000, -1000, 69, 20, -1000, -1000, -1000, 18, -1000,
 	88, 86, 6, -1000, -25, -1000, -1000, -1000,
 }
-var yyPgo = [...]int{
 
+var yyPgo = [...]int{
 	0, 0, 71, 4, 94, 1, 103, 102, 101, 2,
 	100, 99, 3, 98, 97, 10, 96,
 }
-var yyR1 = [...]int{
 
+var yyR1 = [...]int{
 	0, 16, 16, 16, 16, 16, 10, 11, 11, 12,
 	12, 8, 9, 9, 15, 13, 6, 6, 5, 5,
 	14, 14, 14, 1, 1, 1, 1, 1, 3, 3,
 	3, 7, 7, 2, 2, 2, 2, 2, 2, 2,
 	2, 4, 4, 4,
 }
-var yyR2 = [...]int{
 
+var yyR2 = [...]int{
 	0, 2, 5, 3, 3, 3, 2, 3, 1, 0,
 	3, 2, 0, 3, 1, 4, 5, 1, 1, 1,
 	0, 2, 3, 1, 1, 2, 4, 3, 1, 3,
 	4, 1, 3, 1, 3, 3, 3, 3, 3, 3,
 	3, 1, 3, 3,
 }
-var yyChk = [...]int{
 
+var yyChk = [...]int{
 	-1000, -16, -4, 8, 9, 10, 11, -2, -3, -1,
 	4, 5, 29, 25, 17, 18, 5, -10, -15, 4,
 	-13, 5, -8, -1, 22, 7, 31, 12, 13, 24,
@@ -166,8 +168,8 @@ var yyChk = [...]int{
 	25, -12, -12, -14, -5, 4, 5, -9, 28, 5,
 	6, 20, -1, 4, -5, 4, 5, 30,
 }
-var yyDef = [...]int{
 
+var yyDef = [...]int{
 	0, -2, 0, 0, 0, 0, 0, 41, 33, 28,
 	23, 24, 0, 1, 0, 0, 0, 0, 9, 14,
 	0, 0, 0, 12, 0, 25, 0, 0, 0, 0,
@@ -178,8 +180,8 @@ var yyDef = [...]int{
 	2, 7, 10, 15, 0, -2, -2, 13, 0, 21,
 	0, 0, 32, 22, 0, 18, 19, 16,
 }
-var yyTok1 = [...]int{
 
+var yyTok1 = [...]int{
 	1, 3, 3, 3, 3, 3, 3, 3, 3, 3,
 	3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
 	3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
@@ -194,11 +196,12 @@ var yyTok1 = [...]int{
 	3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
 	3, 3, 3, 3, 22,
 }
-var yyTok2 = [...]int{
 
+var yyTok2 = [...]int{
 	2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
 	12, 13, 14, 15, 16, 17, 18, 19, 20,
 }
+
 var yyTok3 = [...]int{
 	0,
 }
@@ -542,87 +545,87 @@ yydefault:
 
 	case 1:
 		yyDollar = yyS[yypt-2 : yypt+1]
-		//line expressions.y:46
+//line expressions.y:46
 		{
 			yylex.(*lexer).val = yyDollar[1].f
 		}
 	case 2:
 		yyDollar = yyS[yypt-5 : yypt+1]
-		//line expressions.y:47
+//line expressions.y:47
 		{
 			yylex.(*lexer).Assignment = Assignment{yyDollar[2].name, &expression{yyDollar[4].f}}
 		}
 	case 3:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:50
+//line expressions.y:50
 		{
 			yylex.(*lexer).Cycle = yyDollar[2].cycle
 		}
 	case 4:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:51
+//line expressions.y:51
 		{
 			yylex.(*lexer).Loop = yyDollar[2].loop
 		}
 	case 5:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:52
+//line expressions.y:52
 		{
 			yylex.(*lexer).When = When{yyDollar[2].exprs}
 		}
 	case 6:
 		yyDollar = yyS[yypt-2 : yypt+1]
-		//line expressions.y:55
+//line expressions.y:55
 		{
 			yyVAL.cycle = yyDollar[2].cyclefn(yyDollar[1].s)
 		}
 	case 7:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:58
+//line expressions.y:58
 		{
 			h, t := yyDollar[2].s, yyDollar[3].ss
 			yyVAL.cyclefn = func(g string) Cycle { return Cycle{g, append([]string{h}, t...)} }
 		}
 	case 8:
 		yyDollar = yyS[yypt-1 : yypt+1]
-		//line expressions.y:62
+//line expressions.y:62
 		{
 			vals := yyDollar[1].ss
 			yyVAL.cyclefn = func(h string) Cycle { return Cycle{Values: append([]string{h}, vals...)} }
 		}
 	case 9:
 		yyDollar = yyS[yypt-0 : yypt+1]
-		//line expressions.y:69
+//line expressions.y:69
 		{
 			yyVAL.ss = []string{}
 		}
 	case 10:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:70
+//line expressions.y:70
 		{
 			yyVAL.ss = append([]string{yyDollar[2].s}, yyDollar[3].ss...)
 		}
 	case 11:
 		yyDollar = yyS[yypt-2 : yypt+1]
-		//line expressions.y:73
+//line expressions.y:73
 		{
 			yyVAL.exprs = append([]Expression{&expression{yyDollar[1].f}}, yyDollar[2].exprs...)
 		}
 	case 12:
 		yyDollar = yyS[yypt-0 : yypt+1]
-		//line expressions.y:75
+//line expressions.y:75
 		{
 			yyVAL.exprs = []Expression{}
 		}
 	case 13:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:76
+//line expressions.y:76
 		{
 			yyVAL.exprs = append([]Expression{&expression{yyDollar[2].f}}, yyDollar[3].exprs...)
 		}
 	case 14:
 		yyDollar = yyS[yypt-1 : yypt+1]
-		//line expressions.y:79
+//line expressions.y:79
 		{
 			s, ok := yyDollar[1].val.(string)
 			if !ok {
@@ -632,40 +635,40 @@ yydefault:
 		}
 	case 15:
 		yyDollar = yyS[yypt-4 : yypt+1]
-		//line expressions.y:87
+//line expressions.y:87
 		{
 			name, expr, mods := yyDollar[1].name, yyDollar[3].f, yyDollar[4].loopmods
 			yyVAL.loop = Loop{name, &expression{expr}, mods}
 		}
 	case 16:
 		yyDollar = yyS[yypt-5 : yypt+1]
-		//line expressions.y:93
+//line expressions.y:93
 		{
 			yyVAL.f = makeRangeExpr(yyDollar[2].f, yyDollar[4].f)
 		}
 	case 18:
 		yyDollar = yyS[yypt-1 : yypt+1]
-		//line expressions.y:101
+//line expressions.y:101
 		{
 			val := yyDollar[1].val
 			yyVAL.f = func(Context) values.Value { return values.ValueOf(val) }
 		}
 	case 19:
 		yyDollar = yyS[yypt-1 : yypt+1]
-		//line expressions.y:102
+//line expressions.y:102
 		{
 			name := yyDollar[1].name
 			yyVAL.f = func(ctx Context) values.Value { return values.ValueOf(ctx.Get(name)) }
 		}
 	case 20:
 		yyDollar = yyS[yypt-0 : yypt+1]
-		//line expressions.y:105
+//line expressions.y:105
 		{
 			yyVAL.loopmods = loopModifiers{Cols: math.MaxUint32}
 		}
 	case 21:
 		yyDollar = yyS[yypt-2 : yypt+1]
-		//line expressions.y:106
+//line expressions.y:106
 		{
 			switch yyDollar[2].name {
 			case "reversed":
@@ -677,7 +680,7 @@ yydefault:
 		}
 	case 22:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:115
+//line expressions.y:115
 		{ // TODO can this be a variable?
 			switch yyDollar[2].name {
 			case "cols":
@@ -705,63 +708,63 @@ yydefault:
 		}
 	case 23:
 		yyDollar = yyS[yypt-1 : yypt+1]
-		//line expressions.y:143
+//line expressions.y:143
 		{
 			val := yyDollar[1].val
 			yyVAL.f = func(Context) values.Value { return values.ValueOf(val) }
 		}
 	case 24:
 		yyDollar = yyS[yypt-1 : yypt+1]
-		//line expressions.y:144
+//line expressions.y:144
 		{
 			name := yyDollar[1].name
 			yyVAL.f = func(ctx Context) values.Value { return values.ValueOf(ctx.Get(name)) }
 		}
 	case 25:
 		yyDollar = yyS[yypt-2 : yypt+1]
-		//line expressions.y:145
+//line expressions.y:145
 		{
 			yyVAL.f = makeObjectPropertyExpr(yyDollar[1].f, yyDollar[2].name)
 		}
 	case 26:
 		yyDollar = yyS[yypt-4 : yypt+1]
-		//line expressions.y:146
+//line expressions.y:146
 		{
 			yyVAL.f = makeIndexExpr(yyDollar[1].f, yyDollar[3].f)
 		}
 	case 27:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:147
+//line expressions.y:147
 		{
 			yyVAL.f = yyDollar[2].f
 		}
 	case 29:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:152
+//line expressions.y:152
 		{
 			yyVAL.f = makeFilter(yyDollar[1].f, yyDollar[3].name, nil)
 		}
 	case 30:
 		yyDollar = yyS[yypt-4 : yypt+1]
-		//line expressions.y:153
+//line expressions.y:153
 		{
 			yyVAL.f = makeFilter(yyDollar[1].f, yyDollar[3].name, yyDollar[4].filter_params)
 		}
 	case 31:
 		yyDollar = yyS[yypt-1 : yypt+1]
-		//line expressions.y:157
+//line expressions.y:157
 		{
 			yyVAL.filter_params = []valueFn{yyDollar[1].f}
 		}
 	case 32:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:159
+//line expressions.y:159
 		{
 			yyVAL.filter_params = append(yyDollar[1].filter_params, yyDollar[3].f)
 		}
 	case 34:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:163
+//line expressions.y:163
 		{
 			fa, fb := yyDollar[1].f, yyDollar[3].f
 			yyVAL.f = func(ctx Context) values.Value {
@@ -771,7 +774,7 @@ yydefault:
 		}
 	case 35:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:170
+//line expressions.y:170
 		{
 			fa, fb := yyDollar[1].f, yyDollar[3].f
 			yyVAL.f = func(ctx Context) values.Value {
@@ -781,7 +784,7 @@ yydefault:
 		}
 	case 36:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:177
+//line expressions.y:177
 		{
 			fa, fb := yyDollar[1].f, yyDollar[3].f
 			yyVAL.f = func(ctx Context) values.Value {
@@ -791,7 +794,7 @@ yydefault:
 		}
 	case 37:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:184
+//line expressions.y:184
 		{
 			fa, fb := yyDollar[1].f, yyDollar[3].f
 			yyVAL.f = func(ctx Context) values.Value {
@@ -801,7 +804,7 @@ yydefault:
 		}
 	case 38:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:191
+//line expressions.y:191
 		{
 			fa, fb := yyDollar[1].f, yyDollar[3].f
 			yyVAL.f = func(ctx Context) values.Value {
@@ -811,7 +814,7 @@ yydefault:
 		}
 	case 39:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:198
+//line expressions.y:198
 		{
 			fa, fb := yyDollar[1].f, yyDollar[3].f
 			yyVAL.f = func(ctx Context) values.Value {
@@ -821,13 +824,13 @@ yydefault:
 		}
 	case 40:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:205
+//line expressions.y:205
 		{
 			yyVAL.f = makeContainsExpr(yyDollar[1].f, yyDollar[3].f)
 		}
 	case 42:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:210
+//line expressions.y:210
 		{
 			fa, fb := yyDollar[1].f, yyDollar[3].f
 			yyVAL.f = func(ctx Context) values.Value {
@@ -836,7 +839,7 @@ yydefault:
 		}
 	case 43:
 		yyDollar = yyS[yypt-3 : yypt+1]
-		//line expressions.y:216
+//line expressions.y:216
 		{
 			fa, fb := yyDollar[1].f, yyDollar[3].f
 			yyVAL.f = func(ctx Context) values.Value {

template_test.go

@@ -105,6 +105,7 @@ func BenchmarkTemplate_Render(b *testing.B) {
 	}
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		tpl.Render(bindings)
+		_, err := tpl.Render(bindings)
+		require.NoError(b, err)
 	}
 }

values/drop_test.go

@@ -56,6 +56,7 @@ func BenchmarkDrop_Resolve_3(b *testing.B) {
 			values <- d.Int()
 		}
 		for i := cap(values); i > 0; i-- {
+			//lint:ignore S1005 TODO look up how else to read the values
 			_ = <-values
 		}
 	}