Create diag package and switch all applicable []tfprotov6.Diagnostic …

…usage (#110)

Create a diag package with a native abstraction for diagnostics, represented as an interface so they can be discriminated between programmatically rather than acting only as practitioner-facing values.

Switch all existing diagnostic usage to the new interface.

Create new diagnostics helpers implementing the new interface.

.changelog/110.txt

@@ -0,0 +1,7 @@
+```release-note:breaking-change
+Most uses of `[]*tfprotov6.Diagnostic` have been replaced with a new `diag.Diagnostics` type. Please update your type signatures, and use one of the `diags.New*` helper functions instead of constructing `*tfprotov6.Diagnostic`s by hand.
+```
+
+```release-note:feature
+Introduced first-class diagnostics (`diag` package).
+```

attr/type.go

@@ -3,7 +3,7 @@ package attr
 import (
 	"context"
 
-	"github.com/hashicorp/terraform-plugin-go/tfprotov6"
+	"github.com/hashicorp/terraform-plugin-framework/diag"
 	"github.com/hashicorp/terraform-plugin-go/tftypes"
 )
 
@@ -80,9 +80,7 @@ type TypeWithValidate interface {
 	// being used to populate the Type. It is generally used to check the
 	// data format and ensure that it complies with the requirements of the
 	// Type.
-	//
-	// TODO: don't use tfprotov6.Diagnostic, use our type
-	Validate(context.Context, tftypes.Value) []*tfprotov6.Diagnostic
+	Validate(context.Context, tftypes.Value) diag.Diagnostics
 }
 
 // TypeWithPlaintextDescription extends the Type interface to include a

diag/attribute_error_diagnostic.go

@@ -0,0 +1,45 @@
+package diag
+
+import (
+	"github.com/hashicorp/terraform-plugin-go/tftypes"
+)
+
+var _ DiagnosticWithPath = AttributeErrorDiagnostic{}
+
+// AttributeErrorDiagnostic is a generic attribute diagnostic with error severity.
+type AttributeErrorDiagnostic struct {
+	ErrorDiagnostic
+
+	path *tftypes.AttributePath
+}
+
+// Equal returns true if the other diagnostic is wholly equivalent.
+func (d AttributeErrorDiagnostic) Equal(other Diagnostic) bool {
+	aed, ok := other.(AttributeErrorDiagnostic)
+
+	if !ok {
+		return false
+	}
+
+	if !aed.Path().Equal(d.Path()) {
+		return false
+	}
+
+	return aed.ErrorDiagnostic.Equal(d.ErrorDiagnostic)
+}
+
+// Path returns the diagnostic path.
+func (d AttributeErrorDiagnostic) Path() *tftypes.AttributePath {
+	return d.path
+}
+
+// NewAttributeErrorDiagnostic returns a new error severity diagnostic with the given summary, detail, and path.
+func NewAttributeErrorDiagnostic(path *tftypes.AttributePath, summary string, detail string) AttributeErrorDiagnostic {
+	return AttributeErrorDiagnostic{
+		ErrorDiagnostic: ErrorDiagnostic{
+			detail:  detail,
+			summary: summary,
+		},
+		path: path,
+	}
+}

diag/attribute_warning_diagnostic.go

@@ -0,0 +1,45 @@
+package diag
+
+import (
+	"github.com/hashicorp/terraform-plugin-go/tftypes"
+)
+
+var _ DiagnosticWithPath = AttributeWarningDiagnostic{}
+
+// AttributeErrorDiagnostic is a generic attribute diagnostic with warning severity.
+type AttributeWarningDiagnostic struct {
+	WarningDiagnostic
+
+	path *tftypes.AttributePath
+}
+
+// Equal returns true if the other diagnostic is wholly equivalent.
+func (d AttributeWarningDiagnostic) Equal(other Diagnostic) bool {
+	awd, ok := other.(AttributeWarningDiagnostic)
+
+	if !ok {
+		return false
+	}
+
+	if !awd.Path().Equal(d.Path()) {
+		return false
+	}
+
+	return awd.WarningDiagnostic.Equal(d.WarningDiagnostic)
+}
+
+// Path returns the diagnostic path.
+func (d AttributeWarningDiagnostic) Path() *tftypes.AttributePath {
+	return d.path
+}
+
+// NewAttributeWarningDiagnostic returns a new warning severity diagnostic with the given summary, detail, and path.
+func NewAttributeWarningDiagnostic(path *tftypes.AttributePath, summary string, detail string) AttributeWarningDiagnostic {
+	return AttributeWarningDiagnostic{
+		WarningDiagnostic: WarningDiagnostic{
+			detail:  detail,
+			summary: summary,
+		},
+		path: path,
+	}
+}

diag/diagnostic.go

@@ -0,0 +1,49 @@
+package diag
+
+import (
+	"github.com/hashicorp/terraform-plugin-go/tftypes"
+)
+
+// Diagnostic is an interface for providing enhanced feedback.
+//
+// These are typically practitioner facing, however it is possible for
+// functionality, such as validation, to use these to change behaviors or
+// otherwise have these be manipulated or removed before being presented.
+//
+// See the ErrorDiagnostic and WarningDiagnostic concrete types for generic
+// implementations.
+type Diagnostic interface {
+	// Severity returns the desired level of feedback for the diagnostic.
+	Severity() Severity
+
+	// Summary is a short description for the diagnostic.
+	//
+	// Typically this is implemented as a title, such as "Invalid Resource Name",
+	// or single line sentence.
+	Summary() string
+
+	// Detail is a long description for the diagnostic.
+	//
+	// This should contain all relevant information about why the diagnostic
+	// was generated and if applicable, ways to prevent the diagnostic. It
+	// should generally be written and formatted for human consumption by
+	// practitioners or provider developers.
+	Detail() string
+
+	// Equal returns true if the other diagnostic is wholly equivalent.
+	Equal(Diagnostic) bool
+}
+
+// DiagnosticWithPath is a diagnostic associated with an attribute path.
+//
+// This attribute information is used to display contextual source configuration
+// to practitioners.
+type DiagnosticWithPath interface {
+	Diagnostic
+
+	// Path points to a specific value within an aggregate value.
+	//
+	// If present, this enables the display of source configuration context for
+	// supporting implementations such as Terraform CLI commands.
+	Path() *tftypes.AttributePath
+}

diag/diagnostic_test.go

@@ -0,0 +1,31 @@
+package diag_test
+
+import (
+	"github.com/hashicorp/terraform-plugin-framework/diag"
+)
+
+var _ diag.Diagnostic = invalidSeverityDiagnostic{}
+
+type invalidSeverityDiagnostic struct{}
+
+func (d invalidSeverityDiagnostic) Detail() string {
+	return "detail for invalid severity diagnostic"
+}
+
+func (d invalidSeverityDiagnostic) Equal(other diag.Diagnostic) bool {
+	isd, ok := other.(invalidSeverityDiagnostic)
+
+	if !ok {
+		return false
+	}
+
+	return isd.Summary() == d.Summary() && isd.Detail() == d.Detail() && isd.Severity() == d.Severity()
+}
+
+func (d invalidSeverityDiagnostic) Severity() diag.Severity {
+	return diag.SeverityInvalid
+}
+
+func (d invalidSeverityDiagnostic) Summary() string {
+	return "summary for invalid severity diagnostic"
+}

diag/diagnostics.go

@@ -0,0 +1,97 @@
+package diag
+
+import (
+	"github.com/hashicorp/terraform-plugin-go/tfprotov6"
+	"github.com/hashicorp/terraform-plugin-go/tftypes"
+)
+
+// Diagnostics represents a collection of diagnostics.
+//
+// While this collection is ordered, the order is not guaranteed as reliable
+// or consistent.
+type Diagnostics []Diagnostic
+
+// AddAttributeError adds a generic attribute error diagnostic to the collection.
+func (diags *Diagnostics) AddAttributeError(path *tftypes.AttributePath, summary string, detail string) {
+	diags.Append(NewAttributeErrorDiagnostic(path, summary, detail))
+}
+
+// AddAttributeWarning adds a generic attribute warning diagnostic to the collection.
+func (diags *Diagnostics) AddAttributeWarning(path *tftypes.AttributePath, summary string, detail string) {
+	diags.Append(NewAttributeWarningDiagnostic(path, summary, detail))
+}
+
+// AddError adds a generic error diagnostic to the collection.
+func (diags *Diagnostics) AddError(summary string, detail string) {
+	diags.Append(NewErrorDiagnostic(summary, detail))
+}
+
+// AddWarning adds a generic warning diagnostic to the collection.
+func (diags *Diagnostics) AddWarning(summary string, detail string) {
+	diags.Append(NewWarningDiagnostic(summary, detail))
+}
+
+// Append adds non-empty and non-duplicate diagnostics to the collection.
+func (diags *Diagnostics) Append(in ...Diagnostic) {
+	for _, diag := range in {
+		if diag == nil {
+			continue
+		}
+
+		if diags.Contains(diag) {
+			continue
+		}
+
+		if diags == nil {
+			*diags = Diagnostics{diag}
+		} else {
+			*diags = append(*diags, diag)
+		}
+	}
+}
+
+// Contains returns true if the collection contains an equal Diagnostic.
+func (diags Diagnostics) Contains(in Diagnostic) bool {
+	for _, diag := range diags {
+		if diag.Equal(in) {
+			return true
+		}
+	}
+
+	return false
+}
+
+// HasError returns true if the collection has an error severity Diagnostic.
+func (diags Diagnostics) HasError() bool {
+	for _, diag := range diags {
+		if diag.Severity() == SeverityError {
+			return true
+		}
+	}
+
+	return false
+}
+
+// ToTfprotov6Diagnostics converts the diagnostics into the tfprotov6 collection type.
+//
+// Usage of this method outside the framework is not supported nor considered
+// for backwards compatibility promises.
+func (diags Diagnostics) ToTfprotov6Diagnostics() []*tfprotov6.Diagnostic {
+	var results []*tfprotov6.Diagnostic
+
+	for _, diag := range diags {
+		tfprotov6Diagnostic := &tfprotov6.Diagnostic{
+			Detail:   diag.Detail(),
+			Severity: diag.Severity().ToTfprotov6DiagnosticSeverity(),
+			Summary:  diag.Summary(),
+		}
+
+		if diagWithPath, ok := diag.(DiagnosticWithPath); ok {
+			tfprotov6Diagnostic.Attribute = diagWithPath.Path()
+		}
+
+		results = append(results, tfprotov6Diagnostic)
+	}
+
+	return results
+}