opentofu/internal/tfdiags/hcl.go
Martin Atkins 8405f46bc5 tfdiags: Expose the "extra information" concept from HCL
HCL's diagnostic model now includes the idea of "extra information" which
works by attaching an initially-opaque interface value to each diagnostic
and then asking callers to type-assert against that value to sniff for
particular interfaces in order to discover additional machine-readable
context about a certain diagnostic message.

This commit echoes that idea into our tfdiags API, for now only for
diagnostics that are backed by an hcl.Diagnostic. All other implementations
of the diagnostic interface just always return nil, which means they never
carry any "extra information".

As is typical for our wrapping abstraction, we have here also a modified
copy of HCL's helper function for conveniently probing a diagnostic for
information of a particular type, designed to work with our diagnostic
interface instead of HCL's concrete diagnostic type.
2022-06-23 13:52:23 -07:00

134 lines
3.2 KiB
Go

package tfdiags
import (
"github.com/hashicorp/hcl/v2"
)
// hclDiagnostic is a Diagnostic implementation that wraps a HCL Diagnostic
type hclDiagnostic struct {
diag *hcl.Diagnostic
}
var _ Diagnostic = hclDiagnostic{}
func (d hclDiagnostic) Severity() Severity {
switch d.diag.Severity {
case hcl.DiagWarning:
return Warning
default:
return Error
}
}
func (d hclDiagnostic) Description() Description {
return Description{
Summary: d.diag.Summary,
Detail: d.diag.Detail,
}
}
func (d hclDiagnostic) Source() Source {
var ret Source
if d.diag.Subject != nil {
rng := SourceRangeFromHCL(*d.diag.Subject)
ret.Subject = &rng
}
if d.diag.Context != nil {
rng := SourceRangeFromHCL(*d.diag.Context)
ret.Context = &rng
}
return ret
}
func (d hclDiagnostic) FromExpr() *FromExpr {
if d.diag.Expression == nil || d.diag.EvalContext == nil {
return nil
}
return &FromExpr{
Expression: d.diag.Expression,
EvalContext: d.diag.EvalContext,
}
}
func (d hclDiagnostic) ExtraInfo() interface{} {
return d.diag.Extra
}
// SourceRangeFromHCL constructs a SourceRange from the corresponding range
// type within the HCL package.
func SourceRangeFromHCL(hclRange hcl.Range) SourceRange {
return SourceRange{
Filename: hclRange.Filename,
Start: SourcePos{
Line: hclRange.Start.Line,
Column: hclRange.Start.Column,
Byte: hclRange.Start.Byte,
},
End: SourcePos{
Line: hclRange.End.Line,
Column: hclRange.End.Column,
Byte: hclRange.End.Byte,
},
}
}
// ToHCL constructs a HCL Range from the receiving SourceRange. This is the
// opposite of SourceRangeFromHCL.
func (r SourceRange) ToHCL() hcl.Range {
return hcl.Range{
Filename: r.Filename,
Start: hcl.Pos{
Line: r.Start.Line,
Column: r.Start.Column,
Byte: r.Start.Byte,
},
End: hcl.Pos{
Line: r.End.Line,
Column: r.End.Column,
Byte: r.End.Byte,
},
}
}
// ToHCL constructs a hcl.Diagnostics containing the same diagnostic messages
// as the receiving tfdiags.Diagnostics.
//
// This conversion preserves the data that HCL diagnostics are able to
// preserve but would be lossy in a round trip from tfdiags to HCL and then
// back to tfdiags, because it will lose the specific type information of
// the source diagnostics. In most cases this will not be a significant
// problem, but could produce an awkward result in some special cases such
// as converting the result of ConsolidateWarnings, which will force the
// resulting warning groups to be flattened early.
func (diags Diagnostics) ToHCL() hcl.Diagnostics {
if len(diags) == 0 {
return nil
}
ret := make(hcl.Diagnostics, len(diags))
for i, diag := range diags {
severity := diag.Severity()
desc := diag.Description()
source := diag.Source()
fromExpr := diag.FromExpr()
hclDiag := &hcl.Diagnostic{
Summary: desc.Summary,
Detail: desc.Detail,
Severity: severity.ToHCL(),
}
if source.Subject != nil {
hclDiag.Subject = source.Subject.ToHCL().Ptr()
}
if source.Context != nil {
hclDiag.Context = source.Context.ToHCL().Ptr()
}
if fromExpr != nil {
hclDiag.Expression = fromExpr.Expression
hclDiag.EvalContext = fromExpr.EvalContext
}
ret[i] = hclDiag
}
return ret
}