1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
|
package typeexpr
import (
"bytes"
"fmt"
"sort"
"github.com/hashicorp/hcl2/hcl/hclsyntax"
"github.com/hashicorp/hcl2/hcl"
"github.com/zclconf/go-cty/cty"
)
// Type attempts to process the given expression as a type expression and, if
// successful, returns the resulting type. If unsuccessful, error diagnostics
// are returned.
func Type(expr hcl.Expression) (cty.Type, hcl.Diagnostics) {
return getType(expr, false)
}
// TypeConstraint attempts to parse the given expression as a type constraint
// and, if successful, returns the resulting type. If unsuccessful, error
// diagnostics are returned.
//
// A type constraint has the same structure as a type, but it additionally
// allows the keyword "any" to represent cty.DynamicPseudoType, which is often
// used as a wildcard in type checking and type conversion operations.
func TypeConstraint(expr hcl.Expression) (cty.Type, hcl.Diagnostics) {
return getType(expr, true)
}
// TypeString returns a string rendering of the given type as it would be
// expected to appear in the HCL native syntax.
//
// This is primarily intended for showing types to the user in an application
// that uses typexpr, where the user can be assumed to be familiar with the
// type expression syntax. In applications that do not use typeexpr these
// results may be confusing to the user and so type.FriendlyName may be
// preferable, even though it's less precise.
//
// TypeString produces reasonable results only for types like what would be
// produced by the Type and TypeConstraint functions. In particular, it cannot
// support capsule types.
func TypeString(ty cty.Type) string {
// Easy cases first
switch ty {
case cty.String:
return "string"
case cty.Bool:
return "bool"
case cty.Number:
return "number"
case cty.DynamicPseudoType:
return "any"
}
if ty.IsCapsuleType() {
panic("TypeString does not support capsule types")
}
if ty.IsCollectionType() {
ety := ty.ElementType()
etyString := TypeString(ety)
switch {
case ty.IsListType():
return fmt.Sprintf("list(%s)", etyString)
case ty.IsSetType():
return fmt.Sprintf("set(%s)", etyString)
case ty.IsMapType():
return fmt.Sprintf("map(%s)", etyString)
default:
// Should never happen because the above is exhaustive
panic("unsupported collection type")
}
}
if ty.IsObjectType() {
var buf bytes.Buffer
buf.WriteString("object({")
atys := ty.AttributeTypes()
names := make([]string, 0, len(atys))
for name := range atys {
names = append(names, name)
}
sort.Strings(names)
first := true
for _, name := range names {
aty := atys[name]
if !first {
buf.WriteByte(',')
}
if !hclsyntax.ValidIdentifier(name) {
// Should never happen for any type produced by this package,
// but we'll do something reasonable here just so we don't
// produce garbage if someone gives us a hand-assembled object
// type that has weird attribute names.
// Using Go-style quoting here isn't perfect, since it doesn't
// exactly match HCL syntax, but it's fine for an edge-case.
buf.WriteString(fmt.Sprintf("%q", name))
} else {
buf.WriteString(name)
}
buf.WriteByte('=')
buf.WriteString(TypeString(aty))
first = false
}
buf.WriteString("})")
return buf.String()
}
if ty.IsTupleType() {
var buf bytes.Buffer
buf.WriteString("tuple([")
etys := ty.TupleElementTypes()
first := true
for _, ety := range etys {
if !first {
buf.WriteByte(',')
}
buf.WriteString(TypeString(ety))
first = false
}
buf.WriteString("])")
return buf.String()
}
// Should never happen because we covered all cases above.
panic(fmt.Errorf("unsupported type %#v", ty))
}
|
