all: remove manual work via //go:generate stringer

Using go run, meaning that we track the x/tools version via go.mod.

Signed-off-by: Daniel Martí <[email protected]>
Change-Id: I4e93f045bb76d3ce00ea004bca2d68d4ee0bf4b2
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1186238
TryBot-Result: CUEcueckoo <[email protected]>
Reviewed-by: Roger Peppe <[email protected]>
Unity-Result: CUE porcuepine <[email protected]>

cue/token/token.go

@@ -16,34 +16,41 @@
 // programming language and basic operations on tokens (printing, predicates).
 package token // import "cuelang.org/go/cue/token"
 
-import "strconv"
-
 // Token is the set of lexical tokens of the CUE configuration language.
 type Token int
 
+//go:generate go run golang.org/x/tools/cmd/stringer -type=Token -linecomment
+
 // The list of tokens.
 const (
 	// Special tokens
 	ILLEGAL Token = iota
 	EOF
 	COMMENT
-	ATTRIBUTE // @foo(bar,baz=4)
+	// e.g. @foo(bar,baz=4)
+	ATTRIBUTE
 
-	literalBeg
 	// Identifiers and basic type literals
 	// (these tokens stand for classes of literals)
-	IDENT // main, _tmp
-	INT   // 12_345Mi, 0700, 0xdeadbeef, 1.2M
-	FLOAT // 123.45,
-	// DURATION // 3m4s TODO
-	STRING        // "abc"
-	INTERPOLATION // a part of a template string, e.g. `"age: \(`
-	BOTTOM        // _|_
+	literalBeg
+	// e.g. main, _tmp
+	IDENT
+	// e.g. 12_345Mi, 0700, 0xdeadbeef, 1.2M
+	INT
+	// e.g. 123.45
+	FLOAT
+	// e.g. 3m4s; TODO
+	// DURATION
+	// e.g. "abc"
+	STRING
+	// a part of a template string, e.g. `"age: \(`
+	INTERPOLATION
+	BOTTOM // _|_
 
 	literalEnd
 
-	operatorBeg
 	// Operators and delimiters
+	operatorBeg
 	ADD // +
 	SUB // -
 	MUL // *
@@ -92,106 +99,20 @@ const (
 
 	keywordBeg
 
-	IF
-	FOR
-	IN
-	LET
-	FUNC // experimental
+	IF  // if
+	FOR // for
+	IN  // in
+	LET // let
+	// experimental
+	FUNC // func
 
-	TRUE
-	FALSE
-	NULL
+	TRUE  // true
+	FALSE // false
+	NULL  // null
 
 	keywordEnd
 )
 
-var tokens = [...]string{
-	ILLEGAL: "ILLEGAL",
-
-	EOF:     "EOF",
-	COMMENT: "COMMENT",
-
-	IDENT:         "IDENT",
-	INT:           "INT",
-	FLOAT:         "FLOAT",
-	STRING:        "STRING",
-	INTERPOLATION: "INTERPOLATION",
-	ATTRIBUTE:     "ATTRIBUTE",
-
-	ADD: "+",
-	SUB: "-",
-	MUL: "*",
-	POW: "^",
-	QUO: "/",
-
-	IQUO: "quo",
-	IREM: "rem",
-	IDIV: "div",
-	IMOD: "mod",
-
-	AND: "&",
-	OR:  "|",
-
-	LAND: "&&",
-	LOR:  "||",
-
-	BIND:  "=",
-	EQL:   "==",
-	LSS:   "<",
-	GTR:   ">",
-	NOT:   "!",
-	ARROW: "<-",
-
-	NEQ: "!=",
-	LEQ: "<=",
-	GEQ: ">=",
-
-	MAT:  "=~",
-	NMAT: "!~",
-
-	LPAREN:   "(",
-	LBRACK:   "[",
-	LBRACE:   "{",
-	COMMA:    ",",
-	PERIOD:   ".",
-	ELLIPSIS: "...",
-
-	RPAREN:    ")",
-	RBRACK:    "]",
-	RBRACE:    "}",
-	SEMICOLON: ";",
-	COLON:     ":",
-	OPTION:    "?",
-
-	BOTTOM: "_|_",
-
-	FALSE: "false",
-	TRUE:  "true",
-	NULL:  "null",
-
-	FOR:  "for",
-	IF:   "if",
-	IN:   "in",
-	LET:  "let",
-	FUNC: "func",
-}
-
-// String returns the string corresponding to the token tok.
-// For operators, delimiters, and keywords the string is the actual
-// token character sequence (e.g., for the token ADD, the string is
-// "+"). For all other tokens the string corresponds to the token
-// constant name (e.g. for the token IDENT, the string is "IDENT").
-func (tok Token) String() string {
-	s := ""
-	if 0 <= tok && tok < Token(len(tokens)) {
-		s = tokens[tok]
-	}
-	if s == "" {
-		s = "token(" + strconv.Itoa(int(tok)) + ")"
-	}
-	return s
-}
-
 // A set of constants for precedence-based expression parsing.
 // Non-operators have lowest precedence, followed by operators
 // starting with precedence 1 up to unary operators. The highest
@@ -236,8 +157,8 @@ var keywords map[string]Token
 
 func init() {
 	keywords = make(map[string]Token)
-	for i := keywordBeg + 1; i < keywordEnd; i++ {
-		keywords[tokens[i]] = i
+	for tok := keywordBeg + 1; tok < keywordEnd; tok++ {
+		keywords[tok.String()] = tok
 	}
 }
 

internal/core/adt/op.go

@@ -20,79 +20,46 @@ import "cuelang.org/go/cue/token"
 // use to evaluate a value.
 type Op int
 
-func (o Op) String() string {
-	return opToString[o]
-}
+//go:generate go run golang.org/x/tools/cmd/stringer -type=Op -linecomment
 
 // Values of Op.
 const (
 	NoOp Op = iota
 
-	AndOp
-	OrOp
-
-	SelectorOp
-	IndexOp
-	SliceOp
-	CallOp
-
-	BoolAndOp
-	BoolOrOp
-
-	EqualOp
-	NotOp
-	NotEqualOp
-	LessThanOp
-	LessEqualOp
-	GreaterThanOp
-	GreaterEqualOp
-
-	MatchOp
-	NotMatchOp
-
-	AddOp
-	SubtractOp
-	MultiplyOp
-	FloatQuotientOp
-	IntQuotientOp
-	IntRemainderOp
-	IntDivideOp
-	IntModuloOp
-
-	InterpolationOp
+	AndOp // &
+	OrOp  // |
+
+	SelectorOp // .
+	IndexOp    // []
+	SliceOp    // [:]
+	CallOp     // ()
+
+	BoolAndOp // &&
+	BoolOrOp  // ||
+
+	EqualOp        // ==
+	NotOp          // !
+	NotEqualOp     // !=
+	LessThanOp     // <
+	LessEqualOp    // <=
+	GreaterThanOp  // >
+	GreaterEqualOp // >=
+
+	MatchOp    // =~
+	NotMatchOp // !~
+
+	AddOp           // +
+	SubtractOp      // -
+	MultiplyOp      // *
+	FloatQuotientOp // /
+	IntQuotientOp   // quo
+	IntRemainderOp  // rem
+	IntDivideOp     // div
+	IntModuloOp     // mod
+
+	InterpolationOp // \()
 )
 
-var opToString = map[Op]string{
-	AndOp:           "&",
-	OrOp:            "|",
-	BoolAndOp:       "&&",
-	BoolOrOp:        "||",
-	EqualOp:         "==",
-	NotOp:           "!",
-	NotEqualOp:      "!=",
-	LessThanOp:      "<",
-	LessEqualOp:     "<=",
-	GreaterThanOp:   ">",
-	GreaterEqualOp:  ">=",
-	MatchOp:         "=~",
-	NotMatchOp:      "!~",
-	AddOp:           "+",
-	SubtractOp:      "-",
-	MultiplyOp:      "*",
-	FloatQuotientOp: "/",
-	IntQuotientOp:   "quo",
-	IntRemainderOp:  "rem",
-	IntDivideOp:     "div",
-	IntModuloOp:     "mod",
-
-	SelectorOp: ".",
-	IndexOp:    "[]",
-	SliceOp:    "[:]",
-	CallOp:     "()",
-
-	InterpolationOp: `\()`,
-}
-
 // OpFromToken converts a token.Token to an Op.
 func OpFromToken(t token.Token) Op {
 	return tokenMap[t]