package typeexpr
import (
"fmt"
"github.com/hashicorp/hcl2/hcl"
"github.com/zclconf/go-cty/cty"
)
const invalidTypeSummary = "Invalid type specification"
// getType is the internal implementation of both Type and TypeConstraint,
// using the passed flag to distinguish. When constraint is false, the "any"
// keyword will produce an error.
func getType(expr hcl.Expression, constraint bool) (cty.Type, hcl.Diagnostics) {
// First we'll try for one of our keywords
kw := hcl.ExprAsKeyword(expr)
switch kw {
case "bool":
return cty.Bool, nil
case "string":
return cty.String, nil
case "number":
return cty.Number, nil
case "any":
if constraint {
return cty.DynamicPseudoType, nil
}
return cty.DynamicPseudoType, hcl.Diagnostics{{
Severity: hcl.DiagError,
Summary: invalidTypeSummary,
Detail: fmt.Sprintf("The keyword %q cannot be used in this type specification: an exact type is required.", kw),
Subject: expr.Range().Ptr(),
}}
case "list", "map", "set":
return cty.DynamicPseudoType, hcl.Diagnostics{{
Severity: hcl.DiagError,
Summary: invalidTypeSummary,
Detail: fmt.Sprintf("The %s type constructor requires one argument specifying the element type.", kw),
Subject: expr.Range().Ptr(),
}}
case "object":
return cty.DynamicPseudoType, hcl.Diagnostics{{
Severity: hcl.DiagError,
Summary: invalidTypeSummary,
Detail: "The object type constructor requires one argument specifying the attribute types and values as a map.",
Subject: expr.Range().Ptr(),
}}
case "tuple":
return cty.DynamicPseudoType, hcl.Diagnostics{{
Severity: hcl.DiagError,
Summary: invalidTypeSummary,
Detail: "The tuple type constructor requires one argument specifying the element types as a list.",
Subject: expr.Range().Ptr(),
}}
case "":
// okay! we'll fall through and try processing as a call, then.
default:
return cty.DynamicPseudoType, hcl.Diagnostics{{
Severity: hcl.DiagError,
Summary: invalidTypeSummary,
Detail: fmt.Sprintf("The keyword %q is not a valid type specification.", kw),
Subject: expr.Range().Ptr(),
}}
}
// If we get down here then our expression isn't just a keyword, so we'll
// try to process it as a call instead.
call, diags := hcl.ExprCall(expr)
if diags.HasErrors() {
return cty.DynamicPseudoType, hcl.Diagnostics{{
Severity: hcl.DiagError,
Summary: invalidTypeSummary,
Detail: "A type specification is either a primitive type keyword (bool, number, string) or a complex type constructor call, like list(string).",
Subject: expr.Range().Ptr(),
}}
}
switch call.Name {
case "bool", "string", "number", "any":
return cty.DynamicPseudoType, hcl.Diagnostics{{
Severity: hcl.DiagError,
Summary: invalidTypeSummary,
Detail: fmt.Sprintf("Primitive type keyword %q does not expect arguments.", call.Name),
Subject: &call.ArgsRange,
}}
}
if len(call.Arguments) != 1 {
contextRange := call.ArgsRange
subjectRange := call.ArgsRange
if len(call.Arguments) > 1 {
// If we have too many arguments (as opposed to too _few_) then
// we'll highlight the extraneous arguments as the diagnostic
// subject.
subjectRange = hcl.RangeBetween(call.Arguments[1].Range(), call.Arguments[len(call.Arguments)-1].Range())
}
switch call.Name {
case "list", "set", "map":
return cty.DynamicPseudoType, hcl.Diagnostics{{
Severity: hcl.DiagError,
Summary: invalidTypeSummary,
Detail: fmt.Sprintf("The %s type constructor requires one argument specifying the element type.", call.Name),
Subject: &subjectRange,
Context: &contextRange,
}}
case "object":
return cty.DynamicPseudoType, hcl.Diagnostics{{
Severity: hcl.DiagError,
Summary: invalidTypeSummary,
Detail: "The object type constructor requires one argument specifying the attribute types and values as a map.",
Subject: &subjectRange,
Context: &contextRange,
}}
case "tuple":
return cty.DynamicPseudoType, hcl.Diagnostics{{
Severity: hcl.DiagError,
Summary: invalidTypeSummary,
Detail: "The tuple type constructor requires one argument specifying the element types as a list.",
Subject: &subjectRange,
Context: &contextRange,
}}
}
}
switch call.Name {
case "list":
ety, diags := getType(call.Arguments[0], constraint)
return cty.List(ety), diags
case "set":
ety, diags := getType(call.Arguments[0], constraint)
return cty.Set(ety), diags
case "map":
ety, diags := getType(call.Arguments[0], constraint)
return cty.Map(ety), diags
case "object":
attrDefs, diags := hcl.ExprMap(call.Arguments[0])
if diags.HasErrors() {
return cty.DynamicPseudoType, hcl.Diagnostics{{
Severity: hcl.DiagError,
Summary: invalidTypeSummary,
Detail: "Object type constructor requires a map whose keys are attribute names and whose values are the corresponding attribute types.",
Subject: call.Arguments[0].Range().Ptr(),
Context: expr.Range().Ptr(),
}}
}
atys := make(map[string]cty.Type)
for _, attrDef := range attrDefs {
attrName := hcl.ExprAsKeyword(attrDef.Key)
if attrName == "" {
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: invalidTypeSummary,
Detail: "Object constructor map keys must be attribute names.",
Subject: attrDef.Key.Range().Ptr(),
Context: expr.Range().Ptr(),
})
continue
}
aty, attrDiags := getType(attrDef.Value, constraint)
diags = append(diags, attrDiags...)
atys[attrName] = aty
}
return cty.Object(atys), diags
case "tuple":
elemDefs, diags := hcl.ExprList(call.Arguments[0])
if diags.HasErrors() {
return cty.DynamicPseudoType, hcl.Diagnostics{{
Severity: hcl.DiagError,
Summary: invalidTypeSummary,
Detail: "Tuple type constructor requires a list of element types.",
Subject: call.Arguments[0].Range().Ptr(),
Context: expr.Range().Ptr(),
}}
}
etys := make([]cty.Type, len(elemDefs))
for i, defExpr := range elemDefs {
ety, elemDiags := getType(defExpr, constraint)
diags = append(diags, elemDiags...)
etys[i] = ety
}
return cty.Tuple(etys), diags
default:
// Can't access call.Arguments in this path because we've not validated
// that it contains exactly one expression here.
return cty.DynamicPseudoType, hcl.Diagnostics{{
Severity: hcl.DiagError,
Summary: invalidTypeSummary,
Detail: fmt.Sprintf("Keyword %q is not a valid type constructor.", call.Name),
Subject: expr.Range().Ptr(),
}}
}
}
