From 2fb6ae28c66618f3c2f0e9fb29ac874fb45b30c6 Mon Sep 17 00:00:00 2001
From: Isabel Andrade <67916678+beandrad@users.noreply.github.com>
Date: Fri, 4 Jun 2021 11:53:43 +0100
Subject: [PATCH] Add `default` variable schema (#53)

To support completion/hover/highlighting for variable `default`.

As part of this change, the `default` attribute was removed from the
variable schema block so that it can be set by the decoder.

Related to hashicorp/terraform-ls#537
---
 internal/schema/0.12/variable_block.go |  5 ----
 internal/schema/0.14/variable_block.go |  5 ----
 schema/schema_merge.go                 | 35 +++++++++++++++++++++++++-
 3 files changed, 34 insertions(+), 11 deletions(-)

diff --git a/internal/schema/0.12/variable_block.go b/internal/schema/0.12/variable_block.go
index ec88dd1d..cc98cc08 100644
--- a/internal/schema/0.12/variable_block.go
+++ b/internal/schema/0.12/variable_block.go
@@ -39,11 +39,6 @@ func variableBlockSchema(v *version.Version) *schema.BlockSchema {
 					IsOptional:  true,
 					Description: lang.Markdown("Type constraint restricting the type of value to accept, e.g. `string` or `list(string)`"),
 				},
-				"default": {
-					Expr:        schema.ExprConstraints{},
-					IsOptional:  true,
-					Description: lang.Markdown("Default value to use when variable is not explicitly set"),
-				},
 			},
 			Blocks: make(map[string]*schema.BlockSchema, 0),
 		},
diff --git a/internal/schema/0.14/variable_block.go b/internal/schema/0.14/variable_block.go
index ab5fbd62..a78e4442 100644
--- a/internal/schema/0.14/variable_block.go
+++ b/internal/schema/0.14/variable_block.go
@@ -38,11 +38,6 @@ var variableBlockSchema = &schema.BlockSchema{
 				IsOptional:  true,
 				Description: lang.Markdown("Type constraint restricting the type of value to accept, e.g. `string` or `list(string)`"),
 			},
-			"default": {
-				Expr:        schema.ExprConstraints{},
-				IsOptional:  true,
-				Description: lang.Markdown("Default value to use when variable is not explicitly set"),
-			},
 			"sensitive": {
 				Expr:        schema.LiteralTypeOnly(cty.Bool),
 				IsOptional:  true,
diff --git a/schema/schema_merge.go b/schema/schema_merge.go
index 65943f23..3ed0e009 100644
--- a/schema/schema_merge.go
+++ b/schema/schema_merge.go
@@ -6,7 +6,7 @@ import (
 	"github.com/hashicorp/go-version"
 	"github.com/hashicorp/hcl-lang/lang"
 	"github.com/hashicorp/hcl-lang/schema"
-	"github.com/hashicorp/terraform-registry-address"
+	tfaddr "github.com/hashicorp/terraform-registry-address"
 	"github.com/hashicorp/terraform-schema/module"
 )
 
@@ -166,9 +166,42 @@ func (m *SchemaMerger) SchemaForModule(meta *module.Meta) (*schema.BodySchema, e
 		}
 	}
 
+	if _, ok := mergedSchema.Blocks["variable"]; ok {
+		mergedSchema.Blocks["variable"].Labels = []*schema.LabelSchema{
+			{
+				Name:        "name",
+				IsDepKey:    true,
+				Description: lang.PlainText("Variable name"),
+			},
+		}
+		mergedSchema.Blocks["variable"].DependentBody = variableDependentBody(meta.Variables)
+	}
 	return mergedSchema, nil
 }
 
+func variableDependentBody(vars map[string]module.Variable) map[schema.SchemaKey]*schema.BodySchema {
+	depBodies := make(map[schema.SchemaKey]*schema.BodySchema)
+
+	for name, mVar := range vars {
+		depKeys := schema.DependencyKeys{
+			Labels: []schema.LabelDependent{
+				{Index: 0, Value: name},
+			},
+		}
+		depBodies[schema.NewSchemaKey(depKeys)] = &schema.BodySchema{
+			Attributes: map[string]*schema.AttributeSchema{
+				"default": {
+					Expr:        schema.ExprConstraints{schema.LiteralTypeExpr{Type: mVar.Type}},
+					IsOptional:  true,
+					Description: lang.Markdown("Default value to use when variable is not explicitly set"),
+				},
+			},
+		}
+	}
+
+	return depBodies
+}
+
 type ProviderReferences map[module.ProviderRef]tfaddr.Provider
 
 func (pr ProviderReferences) ReferencesOfProvider(addr tfaddr.Provider) []module.ProviderRef {