Implement std.trim for string (#684)

* Implement std.trim for string

builtins.go

@@ -1301,6 +1301,15 @@ func builtinEqualsIgnoreCase(i *interpreter, sv1, sv2 value) (value, error) {
 	return makeValueBoolean(strings.EqualFold(s1.getGoString(), s2.getGoString())), nil
 }
 
+func builtinTrim(i *interpreter, strv value) (value, error) {
+	str, err := i.getString(strv)
+	if err != nil {
+		return nil, err
+	}
+	sStr := str.getGoString()
+	return makeValueString(strings.TrimSpace(sStr)), nil
+}
+
 func base64DecodeGoBytes(i *interpreter, str string) ([]byte, error) {
 	strLen := len(str)
 	if strLen%4 != 0 {
@@ -2407,6 +2416,7 @@ var funcBuiltins = buildBuiltinMap([]builtin{
 	&ternaryBuiltin{name: "strReplace", function: builtinStrReplace, params: ast.Identifiers{"str", "from", "to"}},
 	&unaryBuiltin{name: "isEmpty", function: builtinIsEmpty, params: ast.Identifiers{"str"}},
 	&binaryBuiltin{name: "equalsIgnoreCase", function: builtinEqualsIgnoreCase, params: ast.Identifiers{"str1", "str2"}},
+	&unaryBuiltin{name: "trim", function: builtinTrim, params: ast.Identifiers{"str"}},
 	&unaryBuiltin{name: "base64Decode", function: builtinBase64Decode, params: ast.Identifiers{"str"}},
 	&unaryBuiltin{name: "base64DecodeBytes", function: builtinBase64DecodeBytes, params: ast.Identifiers{"str"}},
 	&unaryBuiltin{name: "parseInt", function: builtinParseInt, params: ast.Identifiers{"str"}},

linter/internal/types/stdlib.go

@@ -91,6 +91,7 @@ func prepareStdlib(g *typeGraph) {
 		"format":           g.newSimpleFuncType(stringType, "str", "vals"),
 		"isEmpty":          g.newSimpleFuncType(boolType, "str"),
 		"equalsIgnoreCase": g.newSimpleFuncType(boolType, "str1", "str2"),
+		"trim":             g.newSimpleFuncType(stringType, "str"),
 		// TODO(sbarzowski) Fix when they match the documentation
 		"escapeStringBash":    g.newSimpleFuncType(stringType, "str_"),
 		"escapeStringDollars": g.newSimpleFuncType(stringType, "str_"),
@@ -145,10 +146,10 @@ func prepareStdlib(g *typeGraph) {
 		"maxArray":      g.newFuncType(anyArrayType, []ast.Parameter{required("arr"), optional("keyF")}),
 		"contains":      g.newSimpleFuncType(boolType, "arr", "elem"),
 		// TODO these need test cases written by someone who understands how to make them
-		"all":           g.newSimpleFuncType(boolArrayType, "arr"),
-		"any":           g.newSimpleFuncType(boolArrayType, "arr"),
-		"remove":        g.newSimpleFuncType(anyArrayType, "arr", "elem"),
-		"removeAt":      g.newSimpleFuncType(anyArrayType, "arr", "i"),
+		"all":      g.newSimpleFuncType(boolArrayType, "arr"),
+		"any":      g.newSimpleFuncType(boolArrayType, "arr"),
+		"remove":   g.newSimpleFuncType(anyArrayType, "arr", "elem"),
+		"removeAt": g.newSimpleFuncType(anyArrayType, "arr", "i"),
 
 		// Sets
 

testdata/builtinTrim.golden

@@ -0,0 +1 @@
+"already trimmed string"

testdata/builtinTrim.jsonnet

@@ -0,0 +1 @@
+std.trim("already trimmed string")

testdata/builtinTrim1.golden

@@ -0,0 +1 @@
+"string with spaces on both ends"

testdata/builtinTrim1.jsonnet

@@ -0,0 +1 @@
+std.trim("    string with spaces on both ends     ")

testdata/builtinTrim2.golden

@@ -0,0 +1 @@
+"string with newline character at end"

testdata/builtinTrim2.jsonnet

@@ -0,0 +1 @@
+std.trim("string with newline character at end\n")

testdata/builtinTrim3.golden

@@ -0,0 +1 @@
+"string with tabs at end"

testdata/builtinTrim3.jsonnet

@@ -0,0 +1 @@
+std.trim("string with tabs at end\t\t")

testdata/builtinTrim4.golden

@@ -0,0 +1,10 @@
+RUNTIME ERROR: Unexpected type number, expected string
+-------------------------------------------------
+	testdata/builtinTrim4:1:1-13	$
+
+std.trim(10)
+
+-------------------------------------------------
+	During evaluation	
+
+

testdata/builtinTrim4.jsonnet

@@ -0,0 +1 @@
+std.trim(10)