--- /dev/null
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package typesinternal
+
+//go:generate stringer -type=ErrorCode
+
+type ErrorCode int
+
+// This file defines the error codes that can be produced during type-checking.
+// Collectively, these codes provide an identifier that may be used to
+// implement special handling for certain types of errors.
+//
+// Error codes should be fine-grained enough that the exact nature of the error
+// can be easily determined, but coarse enough that they are not an
+// implementation detail of the type checking algorithm. As a rule-of-thumb,
+// errors should be considered equivalent if there is a theoretical refactoring
+// of the type checker in which they are emitted in exactly one place. For
+// example, the type checker emits different error messages for "too many
+// arguments" and "too few arguments", but one can imagine an alternative type
+// checker where this check instead just emits a single "wrong number of
+// arguments", so these errors should have the same code.
+//
+// Error code names should be as brief as possible while retaining accuracy and
+// distinctiveness. In most cases names should start with an adjective
+// describing the nature of the error (e.g. "invalid", "unused", "misplaced"),
+// and end with a noun identifying the relevant language object. For example,
+// "DuplicateDecl" or "InvalidSliceExpr". For brevity, naming follows the
+// convention that "bad" implies a problem with syntax, and "invalid" implies a
+// problem with types.
+
+const (
+ _ ErrorCode = iota
+
+ // Test is reserved for errors that only apply while in self-test mode.
+ Test
+
+ /* package names */
+
+ // BlankPkgName occurs when a package name is the blank identifier "_".
+ //
+ // Per the spec:
+ // "The PackageName must not be the blank identifier."
+ BlankPkgName
+
+ // MismatchedPkgName occurs when a file's package name doesn't match the
+ // package name already established by other files.
+ MismatchedPkgName
+
+ // InvalidPkgUse occurs when a package identifier is used outside of a
+ // selector expression.
+ //
+ // Example:
+ // import "fmt"
+ //
+ // var _ = fmt
+ InvalidPkgUse
+
+ /* imports */
+
+ // BadImportPath occurs when an import path is not valid.
+ BadImportPath
+
+ // BrokenImport occurs when importing a package fails.
+ //
+ // Example:
+ // import "amissingpackage"
+ BrokenImport
+
+ // ImportCRenamed occurs when the special import "C" is renamed. "C" is a
+ // pseudo-package, and must not be renamed.
+ //
+ // Example:
+ // import _ "C"
+ ImportCRenamed
+
+ // UnusedImport occurs when an import is unused.
+ //
+ // Example:
+ // import "fmt"
+ //
+ // func main() {}
+ UnusedImport
+
+ /* initialization */
+
+ // InvalidInitCycle occurs when an invalid cycle is detected within the
+ // initialization graph.
+ //
+ // Example:
+ // var x int = f()
+ //
+ // func f() int { return x }
+ InvalidInitCycle
+
+ /* decls */
+
+ // DuplicateDecl occurs when an identifier is declared multiple times.
+ //
+ // Example:
+ // var x = 1
+ // var x = 2
+ DuplicateDecl
+
+ // InvalidDeclCycle occurs when a declaration cycle is not valid.
+ //
+ // Example:
+ // import "unsafe"
+ //
+ // type T struct {
+ // a [n]int
+ // }
+ //
+ // var n = unsafe.Sizeof(T{})
+ InvalidDeclCycle
+
+ // InvalidTypeCycle occurs when a cycle in type definitions results in a
+ // type that is not well-defined.
+ //
+ // Example:
+ // import "unsafe"
+ //
+ // type T [unsafe.Sizeof(T{})]int
+ InvalidTypeCycle
+
+ /* decls > const */
+
+ // InvalidConstInit occurs when a const declaration has a non-constant
+ // initializer.
+ //
+ // Example:
+ // var x int
+ // const _ = x
+ InvalidConstInit
+
+ // InvalidConstVal occurs when a const value cannot be converted to its
+ // target type.
+ //
+ // TODO(findleyr): this error code and example are not very clear. Consider
+ // removing it.
+ //
+ // Example:
+ // const _ = 1 << "hello"
+ InvalidConstVal
+
+ // InvalidConstType occurs when the underlying type in a const declaration
+ // is not a valid constant type.
+ //
+ // Example:
+ // const c *int = 4
+ InvalidConstType
+
+ /* decls > var (+ other variable assignment codes) */
+
+ // UntypedNil occurs when the predeclared (untyped) value nil is used to
+ // initialize a variable declared without an explicit type.
+ //
+ // Example:
+ // var x = nil
+ UntypedNil
+
+ // WrongAssignCount occurs when the number of values on the right-hand side
+ // of an assignment or or initialization expression does not match the number
+ // of variables on the left-hand side.
+ //
+ // Example:
+ // var x = 1, 2
+ WrongAssignCount
+
+ // UnassignableOperand occurs when the left-hand side of an assignment is
+ // not assignable.
+ //
+ // Example:
+ // func f() {
+ // const c = 1
+ // c = 2
+ // }
+ UnassignableOperand
+
+ // NoNewVar occurs when a short variable declaration (':=') does not declare
+ // new variables.
+ //
+ // Example:
+ // func f() {
+ // x := 1
+ // x := 2
+ // }
+ NoNewVar
+
+ // MultiValAssignOp occurs when an assignment operation (+=, *=, etc) does
+ // not have single-valued left-hand or right-hand side.
+ //
+ // Per the spec:
+ // "In assignment operations, both the left- and right-hand expression lists
+ // must contain exactly one single-valued expression"
+ //
+ // Example:
+ // func f() int {
+ // x, y := 1, 2
+ // x, y += 1
+ // return x + y
+ // }
+ MultiValAssignOp
+
+ // InvalidIfaceAssign occurs when a value of type T is used as an
+ // interface, but T does not implement a method of the expected interface.
+ //
+ // Example:
+ // type I interface {
+ // f()
+ // }
+ //
+ // type T int
+ //
+ // var x I = T(1)
+ InvalidIfaceAssign
+
+ // InvalidChanAssign occurs when a chan assignment is invalid.
+ //
+ // Per the spec, a value x is assignable to a channel type T if:
+ // "x is a bidirectional channel value, T is a channel type, x's type V and
+ // T have identical element types, and at least one of V or T is not a
+ // defined type."
+ //
+ // Example:
+ // type T1 chan int
+ // type T2 chan int
+ //
+ // var x T1
+ // // Invalid assignment because both types are named
+ // var _ T2 = x
+ InvalidChanAssign
+
+ // IncompatibleAssign occurs when the type of the right-hand side expression
+ // in an assignment cannot be assigned to the type of the variable being
+ // assigned.
+ //
+ // Example:
+ // var x []int
+ // var _ int = x
+ IncompatibleAssign
+
+ // UnaddressableFieldAssign occurs when trying to assign to a struct field
+ // in a map value.
+ //
+ // Example:
+ // func f() {
+ // m := make(map[string]struct{i int})
+ // m["foo"].i = 42
+ // }
+ UnaddressableFieldAssign
+
+ /* decls > type (+ other type expression codes) */
+
+ // NotAType occurs when the identifier used as the underlying type in a type
+ // declaration or the right-hand side of a type alias does not denote a type.
+ //
+ // Example:
+ // var S = 2
+ //
+ // type T S
+ NotAType
+
+ // InvalidArrayLen occurs when an array length is not a constant value.
+ //
+ // Example:
+ // var n = 3
+ // var _ = [n]int{}
+ InvalidArrayLen
+
+ // BlankIfaceMethod occurs when a method name is '_'.
+ //
+ // Per the spec:
+ // "The name of each explicitly specified method must be unique and not
+ // blank."
+ //
+ // Example:
+ // type T interface {
+ // _(int)
+ // }
+ BlankIfaceMethod
+
+ // IncomparableMapKey occurs when a map key type does not support the == and
+ // != operators.
+ //
+ // Per the spec:
+ // "The comparison operators == and != must be fully defined for operands of
+ // the key type; thus the key type must not be a function, map, or slice."
+ //
+ // Example:
+ // var x map[T]int
+ //
+ // type T []int
+ IncomparableMapKey
+
+ // InvalidIfaceEmbed occurs when a non-interface type is embedded in an
+ // interface.
+ //
+ // Example:
+ // type T struct {}
+ //
+ // func (T) m()
+ //
+ // type I interface {
+ // T
+ // }
+ InvalidIfaceEmbed
+
+ // InvalidPtrEmbed occurs when an embedded field is of the pointer form *T,
+ // and T itself is itself a pointer, an unsafe.Pointer, or an interface.
+ //
+ // Per the spec:
+ // "An embedded field must be specified as a type name T or as a pointer to
+ // a non-interface type name *T, and T itself may not be a pointer type."
+ //
+ // Example:
+ // type T *int
+ //
+ // type S struct {
+ // *T
+ // }
+ InvalidPtrEmbed
+
+ /* decls > func and method */
+
+ // BadRecv occurs when a method declaration does not have exactly one
+ // receiver parameter.
+ //
+ // Example:
+ // func () _() {}
+ BadRecv
+
+ // InvalidRecv occurs when a receiver type expression is not of the form T
+ // or *T, or T is a pointer type.
+ //
+ // Example:
+ // type T struct {}
+ //
+ // func (**T) m() {}
+ InvalidRecv
+
+ // DuplicateFieldAndMethod occurs when an identifier appears as both a field
+ // and method name.
+ //
+ // Example:
+ // type T struct {
+ // m int
+ // }
+ //
+ // func (T) m() {}
+ DuplicateFieldAndMethod
+
+ // DuplicateMethod occurs when two methods on the same receiver type have
+ // the same name.
+ //
+ // Example:
+ // type T struct {}
+ // func (T) m() {}
+ // func (T) m(i int) int { return i }
+ DuplicateMethod
+
+ /* decls > special */
+
+ // InvalidBlank occurs when a blank identifier is used as a value or type.
+ //
+ // Per the spec:
+ // "The blank identifier may appear as an operand only on the left-hand side
+ // of an assignment."
+ //
+ // Example:
+ // var x = _
+ InvalidBlank
+
+ // InvalidIota occurs when the predeclared identifier iota is used outside
+ // of a constant declaration.
+ //
+ // Example:
+ // var x = iota
+ InvalidIota
+
+ // MissingInitBody occurs when an init function is missing its body.
+ //
+ // Example:
+ // func init()
+ MissingInitBody
+
+ // InvalidInitSig occurs when an init function declares parameters or
+ // results.
+ //
+ // Example:
+ // func init() int { return 1 }
+ InvalidInitSig
+
+ // InvalidInitDecl occurs when init is declared as anything other than a
+ // function.
+ //
+ // Example:
+ // var init = 1
+ InvalidInitDecl
+
+ // InvalidMainDecl occurs when main is declared as anything other than a
+ // function, in a main package.
+ InvalidMainDecl
+
+ /* exprs */
+
+ // TooManyValues occurs when a function returns too many values for the
+ // expression context in which it is used.
+ //
+ // Example:
+ // func ReturnTwo() (int, int) {
+ // return 1, 2
+ // }
+ //
+ // var x = ReturnTwo()
+ TooManyValues
+
+ // NotAnExpr occurs when a type expression is used where a value expression
+ // is expected.
+ //
+ // Example:
+ // type T struct {}
+ //
+ // func f() {
+ // T
+ // }
+ NotAnExpr
+
+ /* exprs > const */
+
+ // TruncatedFloat occurs when a float constant is truncated to an integer
+ // value.
+ //
+ // Example:
+ // var _ int = 98.6
+ TruncatedFloat
+
+ // NumericOverflow occurs when a numeric constant overflows its target type.
+ //
+ // Example:
+ // var x int8 = 1000
+ NumericOverflow
+
+ /* exprs > operation */
+
+ // UndefinedOp occurs when an operator is not defined for the type(s) used
+ // in an operation.
+ //
+ // Example:
+ // var c = "a" - "b"
+ UndefinedOp
+
+ // MismatchedTypes occurs when operand types are incompatible in a binary
+ // operation.
+ //
+ // Example:
+ // var a = "hello"
+ // var b = 1
+ // var c = a - b
+ MismatchedTypes
+
+ // DivByZero occurs when a division operation is provable at compile
+ // time to be a division by zero.
+ //
+ // Example:
+ // const divisor = 0
+ // var x int = 1/divisor
+ DivByZero
+
+ // NonNumericIncDec occurs when an increment or decrement operator is
+ // applied to a non-numeric value.
+ //
+ // Example:
+ // func f() {
+ // var c = "c"
+ // c++
+ // }
+ NonNumericIncDec
+
+ /* exprs > ptr */
+
+ // UnaddressableOperand occurs when the & operator is applied to an
+ // unaddressable expression.
+ //
+ // Example:
+ // var x = &1
+ UnaddressableOperand
+
+ // InvalidIndirection occurs when a non-pointer value is indirected via the
+ // '*' operator.
+ //
+ // Example:
+ // var x int
+ // var y = *x
+ InvalidIndirection
+
+ /* exprs > [] */
+
+ // NonIndexableOperand occurs when an index operation is applied to a value
+ // that cannot be indexed.
+ //
+ // Example:
+ // var x = 1
+ // var y = x[1]
+ NonIndexableOperand
+
+ // InvalidIndex occurs when an index argument is not of integer type,
+ // negative, or out-of-bounds.
+ //
+ // Example:
+ // var s = [...]int{1,2,3}
+ // var x = s[5]
+ //
+ // Example:
+ // var s = []int{1,2,3}
+ // var _ = s[-1]
+ //
+ // Example:
+ // var s = []int{1,2,3}
+ // var i string
+ // var _ = s[i]
+ InvalidIndex
+
+ // SwappedSliceIndices occurs when constant indices in a slice expression
+ // are decreasing in value.
+ //
+ // Example:
+ // var _ = []int{1,2,3}[2:1]
+ SwappedSliceIndices
+
+ /* operators > slice */
+
+ // NonSliceableOperand occurs when a slice operation is applied to a value
+ // whose type is not sliceable, or is unaddressable.
+ //
+ // Example:
+ // var x = [...]int{1, 2, 3}[:1]
+ //
+ // Example:
+ // var x = 1
+ // var y = 1[:1]
+ NonSliceableOperand
+
+ // InvalidSliceExpr occurs when a three-index slice expression (a[x:y:z]) is
+ // applied to a string.
+ //
+ // Example:
+ // var s = "hello"
+ // var x = s[1:2:3]
+ InvalidSliceExpr
+
+ /* exprs > shift */
+
+ // InvalidShiftCount occurs when the right-hand side of a shift operation is
+ // either non-integer, negative, or too large.
+ //
+ // Example:
+ // var (
+ // x string
+ // y int = 1 << x
+ // )
+ InvalidShiftCount
+
+ // InvalidShiftOperand occurs when the shifted operand is not an integer.
+ //
+ // Example:
+ // var s = "hello"
+ // var x = s << 2
+ InvalidShiftOperand
+
+ /* exprs > chan */
+
+ // InvalidReceive occurs when there is a channel receive from a value that
+ // is either not a channel, or is a send-only channel.
+ //
+ // Example:
+ // func f() {
+ // var x = 1
+ // <-x
+ // }
+ InvalidReceive
+
+ // InvalidSend occurs when there is a channel send to a value that is not a
+ // channel, or is a receive-only channel.
+ //
+ // Example:
+ // func f() {
+ // var x = 1
+ // x <- "hello!"
+ // }
+ InvalidSend
+
+ /* exprs > literal */
+
+ // DuplicateLitKey occurs when an index is duplicated in a slice, array, or
+ // map literal.
+ //
+ // Example:
+ // var _ = []int{0:1, 0:2}
+ //
+ // Example:
+ // var _ = map[string]int{"a": 1, "a": 2}
+ DuplicateLitKey
+
+ // MissingLitKey occurs when a map literal is missing a key expression.
+ //
+ // Example:
+ // var _ = map[string]int{1}
+ MissingLitKey
+
+ // InvalidLitIndex occurs when the key in a key-value element of a slice or
+ // array literal is not an integer constant.
+ //
+ // Example:
+ // var i = 0
+ // var x = []string{i: "world"}
+ InvalidLitIndex
+
+ // OversizeArrayLit occurs when an array literal exceeds its length.
+ //
+ // Example:
+ // var _ = [2]int{1,2,3}
+ OversizeArrayLit
+
+ // MixedStructLit occurs when a struct literal contains a mix of positional
+ // and named elements.
+ //
+ // Example:
+ // var _ = struct{i, j int}{i: 1, 2}
+ MixedStructLit
+
+ // InvalidStructLit occurs when a positional struct literal has an incorrect
+ // number of values.
+ //
+ // Example:
+ // var _ = struct{i, j int}{1,2,3}
+ InvalidStructLit
+
+ // MissingLitField occurs when a struct literal refers to a field that does
+ // not exist on the struct type.
+ //
+ // Example:
+ // var _ = struct{i int}{j: 2}
+ MissingLitField
+
+ // DuplicateLitField occurs when a struct literal contains duplicated
+ // fields.
+ //
+ // Example:
+ // var _ = struct{i int}{i: 1, i: 2}
+ DuplicateLitField
+
+ // UnexportedLitField occurs when a positional struct literal implicitly
+ // assigns an unexported field of an imported type.
+ UnexportedLitField
+
+ // InvalidLitField occurs when a field name is not a valid identifier.
+ //
+ // Example:
+ // var _ = struct{i int}{1: 1}
+ InvalidLitField
+
+ // UntypedLit occurs when a composite literal omits a required type
+ // identifier.
+ //
+ // Example:
+ // type outer struct{
+ // inner struct { i int }
+ // }
+ //
+ // var _ = outer{inner: {1}}
+ UntypedLit
+
+ // InvalidLit occurs when a composite literal expression does not match its
+ // type.
+ //
+ // Example:
+ // type P *struct{
+ // x int
+ // }
+ // var _ = P {}
+ InvalidLit
+
+ /* exprs > selector */
+
+ // AmbiguousSelector occurs when a selector is ambiguous.
+ //
+ // Example:
+ // type E1 struct { i int }
+ // type E2 struct { i int }
+ // type T struct { E1; E2 }
+ //
+ // var x T
+ // var _ = x.i
+ AmbiguousSelector
+
+ // UndeclaredImportedName occurs when a package-qualified identifier is
+ // undeclared by the imported package.
+ //
+ // Example:
+ // import "go/types"
+ //
+ // var _ = types.NotAnActualIdentifier
+ UndeclaredImportedName
+
+ // UnexportedName occurs when a selector refers to an unexported identifier
+ // of an imported package.
+ //
+ // Example:
+ // import "reflect"
+ //
+ // type _ reflect.flag
+ UnexportedName
+
+ // UndeclaredName occurs when an identifier is not declared in the current
+ // scope.
+ //
+ // Example:
+ // var x T
+ UndeclaredName
+
+ // MissingFieldOrMethod occurs when a selector references a field or method
+ // that does not exist.
+ //
+ // Example:
+ // type T struct {}
+ //
+ // var x = T{}.f
+ MissingFieldOrMethod
+
+ /* exprs > ... */
+
+ // BadDotDotDotSyntax occurs when a "..." occurs in a context where it is
+ // not valid.
+ //
+ // Example:
+ // var _ = map[int][...]int{0: {}}
+ BadDotDotDotSyntax
+
+ // NonVariadicDotDotDot occurs when a "..." is used on the final argument to
+ // a non-variadic function.
+ //
+ // Example:
+ // func printArgs(s []string) {
+ // for _, a := range s {
+ // println(a)
+ // }
+ // }
+ //
+ // func f() {
+ // s := []string{"a", "b", "c"}
+ // printArgs(s...)
+ // }
+ NonVariadicDotDotDot
+
+ // MisplacedDotDotDot occurs when a "..." is used somewhere other than the
+ // final argument to a function call.
+ //
+ // Example:
+ // func printArgs(args ...int) {
+ // for _, a := range args {
+ // println(a)
+ // }
+ // }
+ //
+ // func f() {
+ // a := []int{1,2,3}
+ // printArgs(0, a...)
+ // }
+ MisplacedDotDotDot
+
+ // InvalidDotDotDotOperand occurs when a "..." operator is applied to a
+ // single-valued operand.
+ //
+ // Example:
+ // func printArgs(args ...int) {
+ // for _, a := range args {
+ // println(a)
+ // }
+ // }
+ //
+ // func f() {
+ // a := 1
+ // printArgs(a...)
+ // }
+ //
+ // Example:
+ // func args() (int, int) {
+ // return 1, 2
+ // }
+ //
+ // func printArgs(args ...int) {
+ // for _, a := range args {
+ // println(a)
+ // }
+ // }
+ //
+ // func g() {
+ // printArgs(args()...)
+ // }
+ InvalidDotDotDotOperand
+
+ // InvalidDotDotDot occurs when a "..." is used in a non-variadic built-in
+ // function.
+ //
+ // Example:
+ // var s = []int{1, 2, 3}
+ // var l = len(s...)
+ InvalidDotDotDot
+
+ /* exprs > built-in */
+
+ // UncalledBuiltin occurs when a built-in function is used as a
+ // function-valued expression, instead of being called.
+ //
+ // Per the spec:
+ // "The built-in functions do not have standard Go types, so they can only
+ // appear in call expressions; they cannot be used as function values."
+ //
+ // Example:
+ // var _ = copy
+ UncalledBuiltin
+
+ // InvalidAppend occurs when append is called with a first argument that is
+ // not a slice.
+ //
+ // Example:
+ // var _ = append(1, 2)
+ InvalidAppend
+
+ // InvalidCap occurs when an argument to the cap built-in function is not of
+ // supported type.
+ //
+ // See https://golang.org/ref/spec#Lengthand_capacity for information on
+ // which underlying types are supported as arguments to cap and len.
+ //
+ // Example:
+ // var s = 2
+ // var x = cap(s)
+ InvalidCap
+
+ // InvalidClose occurs when close(...) is called with an argument that is
+ // not of channel type, or that is a receive-only channel.
+ //
+ // Example:
+ // func f() {
+ // var x int
+ // close(x)
+ // }
+ InvalidClose
+
+ // InvalidCopy occurs when the arguments are not of slice type or do not
+ // have compatible type.
+ //
+ // See https://golang.org/ref/spec#Appendingand_copying_slices for more
+ // information on the type requirements for the copy built-in.
+ //
+ // Example:
+ // func f() {
+ // var x []int
+ // y := []int64{1,2,3}
+ // copy(x, y)
+ // }
+ InvalidCopy
+
+ // InvalidComplex occurs when the complex built-in function is called with
+ // arguments with incompatible types.
+ //
+ // Example:
+ // var _ = complex(float32(1), float64(2))
+ InvalidComplex
+
+ // InvalidDelete occurs when the delete built-in function is called with a
+ // first argument that is not a map.
+ //
+ // Example:
+ // func f() {
+ // m := "hello"
+ // delete(m, "e")
+ // }
+ InvalidDelete
+
+ // InvalidImag occurs when the imag built-in function is called with an
+ // argument that does not have complex type.
+ //
+ // Example:
+ // var _ = imag(int(1))
+ InvalidImag
+
+ // InvalidLen occurs when an argument to the len built-in function is not of
+ // supported type.
+ //
+ // See https://golang.org/ref/spec#Lengthand_capacity for information on
+ // which underlying types are supported as arguments to cap and len.
+ //
+ // Example:
+ // var s = 2
+ // var x = len(s)
+ InvalidLen
+
+ // SwappedMakeArgs occurs when make is called with three arguments, and its
+ // length argument is larger than its capacity argument.
+ //
+ // Example:
+ // var x = make([]int, 3, 2)
+ SwappedMakeArgs
+
+ // InvalidMake occurs when make is called with an unsupported type argument.
+ //
+ // See https://golang.org/ref/spec#Makingslices_maps_and_channels for
+ // information on the types that may be created using make.
+ //
+ // Example:
+ // var x = make(int)
+ InvalidMake
+
+ // InvalidReal occurs when the real built-in function is called with an
+ // argument that does not have complex type.
+ //
+ // Example:
+ // var _ = real(int(1))
+ InvalidReal
+
+ /* exprs > assertion */
+
+ // InvalidAssert occurs when a type assertion is applied to a
+ // value that is not of interface type.
+ //
+ // Example:
+ // var x = 1
+ // var _ = x.(float64)
+ InvalidAssert
+
+ // ImpossibleAssert occurs for a type assertion x.(T) when the value x of
+ // interface cannot have dynamic type T, due to a missing or mismatching
+ // method on T.
+ //
+ // Example:
+ // type T int
+ //
+ // func (t *T) m() int { return int(*t) }
+ //
+ // type I interface { m() int }
+ //
+ // var x I
+ // var _ = x.(T)
+ ImpossibleAssert
+
+ /* exprs > conversion */
+
+ // InvalidConversion occurs when the argument type cannot be converted to the
+ // target.
+ //
+ // See https://golang.org/ref/spec#Conversions for the rules of
+ // convertibility.
+ //
+ // Example:
+ // var x float64
+ // var _ = string(x)
+ InvalidConversion
+
+ // InvalidUntypedConversion occurs when an there is no valid implicit
+ // conversion from an untyped value satisfying the type constraints of the
+ // context in which it is used.
+ //
+ // Example:
+ // var _ = 1 + ""
+ InvalidUntypedConversion
+
+ /* offsetof */
+
+ // BadOffsetofSyntax occurs when unsafe.Offsetof is called with an argument
+ // that is not a selector expression.
+ //
+ // Example:
+ // import "unsafe"
+ //
+ // var x int
+ // var _ = unsafe.Offsetof(x)
+ BadOffsetofSyntax
+
+ // InvalidOffsetof occurs when unsafe.Offsetof is called with a method
+ // selector, rather than a field selector, or when the field is embedded via
+ // a pointer.
+ //
+ // Per the spec:
+ //
+ // "If f is an embedded field, it must be reachable without pointer
+ // indirections through fields of the struct. "
+ //
+ // Example:
+ // import "unsafe"
+ //
+ // type T struct { f int }
+ // type S struct { *T }
+ // var s S
+ // var _ = unsafe.Offsetof(s.f)
+ //
+ // Example:
+ // import "unsafe"
+ //
+ // type S struct{}
+ //
+ // func (S) m() {}
+ //
+ // var s S
+ // var _ = unsafe.Offsetof(s.m)
+ InvalidOffsetof
+
+ /* control flow > scope */
+
+ // UnusedExpr occurs when a side-effect free expression is used as a
+ // statement. Such a statement has no effect.
+ //
+ // Example:
+ // func f(i int) {
+ // i*i
+ // }
+ UnusedExpr
+
+ // UnusedVar occurs when a variable is declared but unused.
+ //
+ // Example:
+ // func f() {
+ // x := 1
+ // }
+ UnusedVar
+
+ // MissingReturn occurs when a function with results is missing a return
+ // statement.
+ //
+ // Example:
+ // func f() int {}
+ MissingReturn
+
+ // WrongResultCount occurs when a return statement returns an incorrect
+ // number of values.
+ //
+ // Example:
+ // func ReturnOne() int {
+ // return 1, 2
+ // }
+ WrongResultCount
+
+ // OutOfScopeResult occurs when the name of a value implicitly returned by
+ // an empty return statement is shadowed in a nested scope.
+ //
+ // Example:
+ // func factor(n int) (i int) {
+ // for i := 2; i < n; i++ {
+ // if n%i == 0 {
+ // return
+ // }
+ // }
+ // return 0
+ // }
+ OutOfScopeResult
+
+ /* control flow > if */
+
+ // InvalidCond occurs when an if condition is not a boolean expression.
+ //
+ // Example:
+ // func checkReturn(i int) {
+ // if i {
+ // panic("non-zero return")
+ // }
+ // }
+ InvalidCond
+
+ /* control flow > for */
+
+ // InvalidPostDecl occurs when there is a declaration in a for-loop post
+ // statement.
+ //
+ // Example:
+ // func f() {
+ // for i := 0; i < 10; j := 0 {}
+ // }
+ InvalidPostDecl
+
+ // InvalidChanRange occurs when a send-only channel used in a range
+ // expression.
+ //
+ // Example:
+ // func sum(c chan<- int) {
+ // s := 0
+ // for i := range c {
+ // s += i
+ // }
+ // }
+ InvalidChanRange
+
+ // InvalidIterVar occurs when two iteration variables are used while ranging
+ // over a channel.
+ //
+ // Example:
+ // func f(c chan int) {
+ // for k, v := range c {
+ // println(k, v)
+ // }
+ // }
+ InvalidIterVar
+
+ // InvalidRangeExpr occurs when the type of a range expression is not array,
+ // slice, string, map, or channel.
+ //
+ // Example:
+ // func f(i int) {
+ // for j := range i {
+ // println(j)
+ // }
+ // }
+ InvalidRangeExpr
+
+ /* control flow > switch */
+
+ // MisplacedBreak occurs when a break statement is not within a for, switch,
+ // or select statement of the innermost function definition.
+ //
+ // Example:
+ // func f() {
+ // break
+ // }
+ MisplacedBreak
+
+ // MisplacedContinue occurs when a continue statement is not within a for
+ // loop of the innermost function definition.
+ //
+ // Example:
+ // func sumeven(n int) int {
+ // proceed := func() {
+ // continue
+ // }
+ // sum := 0
+ // for i := 1; i <= n; i++ {
+ // if i % 2 != 0 {
+ // proceed()
+ // }
+ // sum += i
+ // }
+ // return sum
+ // }
+ MisplacedContinue
+
+ // MisplacedFallthrough occurs when a fallthrough statement is not within an
+ // expression switch.
+ //
+ // Example:
+ // func typename(i interface{}) string {
+ // switch i.(type) {
+ // case int64:
+ // fallthrough
+ // case int:
+ // return "int"
+ // }
+ // return "unsupported"
+ // }
+ MisplacedFallthrough
+
+ // DuplicateCase occurs when a type or expression switch has duplicate
+ // cases.
+ //
+ // Example:
+ // func printInt(i int) {
+ // switch i {
+ // case 1:
+ // println("one")
+ // case 1:
+ // println("One")
+ // }
+ // }
+ DuplicateCase
+
+ // DuplicateDefault occurs when a type or expression switch has multiple
+ // default clauses.
+ //
+ // Example:
+ // func printInt(i int) {
+ // switch i {
+ // case 1:
+ // println("one")
+ // default:
+ // println("One")
+ // default:
+ // println("1")
+ // }
+ // }
+ DuplicateDefault
+
+ // BadTypeKeyword occurs when a .(type) expression is used anywhere other
+ // than a type switch.
+ //
+ // Example:
+ // type I interface {
+ // m()
+ // }
+ // var t I
+ // var _ = t.(type)
+ BadTypeKeyword
+
+ // InvalidTypeSwitch occurs when .(type) is used on an expression that is
+ // not of interface type.
+ //
+ // Example:
+ // func f(i int) {
+ // switch x := i.(type) {}
+ // }
+ InvalidTypeSwitch
+
+ /* control flow > select */
+
+ // InvalidSelectCase occurs when a select case is not a channel send or
+ // receive.
+ //
+ // Example:
+ // func checkChan(c <-chan int) bool {
+ // select {
+ // case c:
+ // return true
+ // default:
+ // return false
+ // }
+ // }
+ InvalidSelectCase
+
+ /* control flow > labels and jumps */
+
+ // UndeclaredLabel occurs when an undeclared label is jumped to.
+ //
+ // Example:
+ // func f() {
+ // goto L
+ // }
+ UndeclaredLabel
+
+ // DuplicateLabel occurs when a label is declared more than once.
+ //
+ // Example:
+ // func f() int {
+ // L:
+ // L:
+ // return 1
+ // }
+ DuplicateLabel
+
+ // MisplacedLabel occurs when a break or continue label is not on a for,
+ // switch, or select statement.
+ //
+ // Example:
+ // func f() {
+ // L:
+ // a := []int{1,2,3}
+ // for _, e := range a {
+ // if e > 10 {
+ // break L
+ // }
+ // println(a)
+ // }
+ // }
+ MisplacedLabel
+
+ // UnusedLabel occurs when a label is declared but not used.
+ //
+ // Example:
+ // func f() {
+ // L:
+ // }
+ UnusedLabel
+
+ // JumpOverDecl occurs when a label jumps over a variable declaration.
+ //
+ // Example:
+ // func f() int {
+ // goto L
+ // x := 2
+ // L:
+ // x++
+ // return x
+ // }
+ JumpOverDecl
+
+ // JumpIntoBlock occurs when a forward jump goes to a label inside a nested
+ // block.
+ //
+ // Example:
+ // func f(x int) {
+ // goto L
+ // if x > 0 {
+ // L:
+ // print("inside block")
+ // }
+ // }
+ JumpIntoBlock
+
+ /* control flow > calls */
+
+ // InvalidMethodExpr occurs when a pointer method is called but the argument
+ // is not addressable.
+ //
+ // Example:
+ // type T struct {}
+ //
+ // func (*T) m() int { return 1 }
+ //
+ // var _ = T.m(T{})
+ InvalidMethodExpr
+
+ // WrongArgCount occurs when too few or too many arguments are passed by a
+ // function call.
+ //
+ // Example:
+ // func f(i int) {}
+ // var x = f()
+ WrongArgCount
+
+ // InvalidCall occurs when an expression is called that is not of function
+ // type.
+ //
+ // Example:
+ // var x = "x"
+ // var y = x()
+ InvalidCall
+
+ /* control flow > suspended */
+
+ // UnusedResults occurs when a restricted expression-only built-in function
+ // is suspended via go or defer. Such a suspension discards the results of
+ // these side-effect free built-in functions, and therefore is ineffectual.
+ //
+ // Example:
+ // func f(a []int) int {
+ // defer len(a)
+ // return i
+ // }
+ UnusedResults
+
+ // InvalidDefer occurs when a deferred expression is not a function call,
+ // for example if the expression is a type conversion.
+ //
+ // Example:
+ // func f(i int) int {
+ // defer int32(i)
+ // return i
+ // }
+ InvalidDefer
+
+ // InvalidGo occurs when a go expression is not a function call, for example
+ // if the expression is a type conversion.
+ //
+ // Example:
+ // func f(i int) int {
+ // go int32(i)
+ // return i
+ // }
+ InvalidGo
+)
projects / dotfiles / .git / blobdiff