blob: 6063e2bc85cbcaccd3585b4dc5193f0d96c286cc [file] [log] [blame] [edit]
package transform
import (
"github.com/hashicorp/hcl/v2"
)
// NewErrorBody returns a hcl.Body that returns the given diagnostics whenever
// any of its content-access methods are called.
//
// The given diagnostics must have at least one diagnostic of severity
// hcl.DiagError, or this function will panic.
//
// This can be used to prepare a return value for a Transformer that
// can't complete due to an error. While the transform itself will succeed,
// the error will be returned as soon as a caller attempts to extract content
// from the resulting body.
func NewErrorBody(diags hcl.Diagnostics) hcl.Body {
if !diags.HasErrors() {
panic("NewErrorBody called without any error diagnostics")
}
return diagBody{
Diags: diags,
}
}
// BodyWithDiagnostics returns a hcl.Body that wraps another hcl.Body
// and emits the given diagnostics for any content-extraction method.
//
// Unlike the result of NewErrorBody, a body with diagnostics still runs
// the extraction actions on the underlying body if (and only if) the given
// diagnostics do not contain errors, but prepends the given diagnostics with
// any diagnostics produced by the action.
//
// If the given diagnostics is empty, the given body is returned verbatim.
//
// This function is intended for conveniently reporting errors and/or warnings
// produced during a transform, ensuring that they will be seen when the
// caller eventually extracts content from the returned body.
func BodyWithDiagnostics(body hcl.Body, diags hcl.Diagnostics) hcl.Body {
if len(diags) == 0 {
// nothing to do!
return body
}
return diagBody{
Diags: diags,
Wrapped: body,
}
}
type diagBody struct {
Diags hcl.Diagnostics
Wrapped hcl.Body
}
func (b diagBody) Content(schema *hcl.BodySchema) (*hcl.BodyContent, hcl.Diagnostics) {
if b.Diags.HasErrors() {
return b.emptyContent(), b.Diags
}
content, wrappedDiags := b.Wrapped.Content(schema)
diags := make(hcl.Diagnostics, 0, len(b.Diags)+len(wrappedDiags))
diags = append(diags, b.Diags...)
diags = append(diags, wrappedDiags...)
return content, diags
}
func (b diagBody) PartialContent(schema *hcl.BodySchema) (*hcl.BodyContent, hcl.Body, hcl.Diagnostics) {
if b.Diags.HasErrors() {
return b.emptyContent(), b.Wrapped, b.Diags
}
content, remain, wrappedDiags := b.Wrapped.PartialContent(schema)
diags := make(hcl.Diagnostics, 0, len(b.Diags)+len(wrappedDiags))
diags = append(diags, b.Diags...)
diags = append(diags, wrappedDiags...)
return content, remain, diags
}
func (b diagBody) JustAttributes() (hcl.Attributes, hcl.Diagnostics) {
if b.Diags.HasErrors() {
return nil, b.Diags
}
attributes, wrappedDiags := b.Wrapped.JustAttributes()
diags := make(hcl.Diagnostics, 0, len(b.Diags)+len(wrappedDiags))
diags = append(diags, b.Diags...)
diags = append(diags, wrappedDiags...)
return attributes, diags
}
func (b diagBody) MissingItemRange() hcl.Range {
if b.Wrapped != nil {
return b.Wrapped.MissingItemRange()
}
// Placeholder. This should never be seen in practice because decoding
// a diagBody without a wrapped body should always produce an error.
return hcl.Range{
Filename: "<empty>",
}
}
func (b diagBody) emptyContent() *hcl.BodyContent {
return &hcl.BodyContent{
MissingItemRange: b.MissingItemRange(),
}
}