apply opentofu patches (#3)

Author: i4ki

ext/dynblock/expr_wrap.go

@@ -46,6 +46,13 @@ func (e exprWrap) Variables() []hcl.Traversal {
 	return ret
 }
 
+func (e exprWrap) Functions() []hcl.Traversal {
+	if fexpr, ok := e.Expression.(hcl.ExpressionWithFunctions); ok {
+		return fexpr.Functions()
+	}
+	return nil
+}
+
 func (e exprWrap) Value(ctx *hcl.EvalContext) (cty.Value, hcl.Diagnostics) {
 	if e.i == nil {
 		// If we don't have an active iteration then we can just use the

ext/dynblock/functions.go

@@ -0,0 +1,228 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
+package dynblock
+
+import (
+	"github.com/terramate-io/hcl/v2"
+	"github.com/terramate-io/hcl/v2/hclsyntax"
+	"github.com/zclconf/go-cty/cty"
+)
+
+// This is duplicated from ext/dynblock/variables.go and modified to suit functions
+
+// WalkFunctions begins the recursive process of walking all expressions and
+// nested blocks in the given body and its child bodies while taking into
+// account any "dynamic" blocks.
+//
+// This function requires that the caller walk through the nested block
+// structure in the given body level-by-level so that an appropriate schema
+// can be provided at each level to inform further processing. This workflow
+// is thus easiest to use for calling applications that have some higher-level
+// schema representation available with which to drive this multi-step
+// process. If your application uses the hcldec package, you may be able to
+// use FunctionsHCLDec instead for a more automatic approach.
+func WalkFunctions(body hcl.Body) WalkFunctionsNode {
+	return WalkFunctionsNode{
+		body:           body,
+		includeContent: true,
+	}
+}
+
+// WalkExpandFunctions is like Functions but it includes only the functions
+// required for successful block expansion, ignoring any functions referenced
+// inside block contents. The result is the minimal set of all functions
+// required for a call to Expand, excluding functions that would only be
+// needed to subsequently call Content or PartialContent on the expanded
+// body.
+func WalkExpandFunctions(body hcl.Body) WalkFunctionsNode {
+	return WalkFunctionsNode{
+		body: body,
+	}
+}
+
+type WalkFunctionsNode struct {
+	body hcl.Body
+	it   *iteration
+
+	includeContent bool
+}
+
+type WalkFunctionsChild struct {
+	BlockTypeName string
+	Node          WalkFunctionsNode
+}
+
+// Body returns the HCL Body associated with the child node, in case the caller
+// wants to do some sort of inspection of it in order to decide what schema
+// to pass to Visit.
+//
+// Most implementations should just fetch a fixed schema based on the
+// BlockTypeName field and not access this. Deciding on a schema dynamically
+// based on the body is a strange thing to do and generally necessary only if
+// your caller is already doing other bizarre things with HCL bodies.
+func (c WalkFunctionsChild) Body() hcl.Body {
+	return c.Node.body
+}
+
+// exprFunctions handles the
+func exprFunctions(expr hcl.Expression) []hcl.Traversal {
+	if ef, ok := expr.(hcl.ExpressionWithFunctions); ok {
+		return ef.Functions()
+	}
+	// hclsyntax Fallback
+	if hsexpr, ok := expr.(hclsyntax.Expression); ok {
+		return hclsyntax.Functions(hsexpr)
+	}
+	// Not exposed
+	return nil
+}
+
+// Visit returns the function traversals required for any "dynamic" blocks
+// directly in the body associated with this node, and also returns any child
+// nodes that must be visited in order to continue the walk.
+//
+// Each child node has its associated block type name given in its BlockTypeName
+// field, which the calling application should use to determine the appropriate
+// schema for the content of each child node and pass it to the child node's
+// own Visit method to continue the walk recursively.
+func (n WalkFunctionsNode) Visit(schema *hcl.BodySchema) (vars []hcl.Traversal, children []WalkFunctionsChild) {
+	extSchema := n.extendSchema(schema)
+	container, _, _ := n.body.PartialContent(extSchema)
+	if container == nil {
+		return vars, children
+	}
+
+	children = make([]WalkFunctionsChild, 0, len(container.Blocks))
+
+	if n.includeContent {
+		for _, attr := range container.Attributes {
+			for _, traversal := range exprFunctions(attr.Expr) {
+				var ours, inherited bool
+				if n.it != nil {
+					ours = traversal.RootName() == n.it.IteratorName
+					_, inherited = n.it.Inherited[traversal.RootName()]
+				}
+
+				if !(ours || inherited) {
+					vars = append(vars, traversal)
+				}
+			}
+		}
+	}
+
+	for _, block := range container.Blocks {
+		switch block.Type {
+
+		case "dynamic":
+			blockTypeName := block.Labels[0]
+			inner, _, _ := block.Body.PartialContent(functionDetectionInnerSchema)
+			if inner == nil {
+				continue
+			}
+
+			iteratorName := blockTypeName
+			if attr, exists := inner.Attributes["iterator"]; exists {
+				iterTraversal, _ := hcl.AbsTraversalForExpr(attr.Expr)
+				if len(iterTraversal) == 0 {
+					// Ignore this invalid dynamic block, since it'll produce
+					// an error if someone tries to extract content from it
+					// later anyway.
+					continue
+				}
+				iteratorName = iterTraversal.RootName()
+			}
+			blockIt := n.it.MakeChild(iteratorName, cty.DynamicVal, cty.DynamicVal)
+
+			if attr, exists := inner.Attributes["for_each"]; exists {
+				// Filter out iterator names inherited from parent blocks
+				for _, traversal := range exprFunctions(attr.Expr) {
+					if _, inherited := blockIt.Inherited[traversal.RootName()]; !inherited {
+						vars = append(vars, traversal)
+					}
+				}
+			}
+			if attr, exists := inner.Attributes["labels"]; exists {
+				// Filter out both our own iterator name _and_ those inherited
+				// from parent blocks, since we provide _both_ of these to the
+				// label expressions.
+				for _, traversal := range exprFunctions(attr.Expr) {
+					ours := traversal.RootName() == iteratorName
+					_, inherited := blockIt.Inherited[traversal.RootName()]
+
+					if !(ours || inherited) {
+						vars = append(vars, traversal)
+					}
+				}
+			}
+
+			for _, contentBlock := range inner.Blocks {
+				// We only request "content" blocks in our schema, so we know
+				// any blocks we find here will be content blocks. We require
+				// exactly one content block for actual expansion, but we'll
+				// be more liberal here so that callers can still collect
+				// functions from erroneous "dynamic" blocks.
+				children = append(children, WalkFunctionsChild{
+					BlockTypeName: blockTypeName,
+					Node: WalkFunctionsNode{
+						body:           contentBlock.Body,
+						it:             blockIt,
+						includeContent: n.includeContent,
+					},
+				})
+			}
+
+		default:
+			children = append(children, WalkFunctionsChild{
+				BlockTypeName: block.Type,
+				Node: WalkFunctionsNode{
+					body:           block.Body,
+					it:             n.it,
+					includeContent: n.includeContent,
+				},
+			})
+
+		}
+	}
+
+	return vars, children
+}
+
+func (n WalkFunctionsNode) extendSchema(schema *hcl.BodySchema) *hcl.BodySchema {
+	// We augment the requested schema to also include our special "dynamic"
+	// block type, since then we'll get instances of it interleaved with
+	// all of the literal child blocks we must also include.
+	extSchema := &hcl.BodySchema{
+		Attributes: schema.Attributes,
+		Blocks:     make([]hcl.BlockHeaderSchema, len(schema.Blocks), len(schema.Blocks)+1),
+	}
+	copy(extSchema.Blocks, schema.Blocks)
+	extSchema.Blocks = append(extSchema.Blocks, dynamicBlockHeaderSchema)
+
+	return extSchema
+}
+
+// This is a more relaxed schema than what's in schema.go, since we
+// want to maximize the amount of functions we can find even if there
+// are erroneous blocks.
+var functionDetectionInnerSchema = &hcl.BodySchema{
+	Attributes: []hcl.AttributeSchema{
+		{
+			Name:     "for_each",
+			Required: false,
+		},
+		{
+			Name:     "labels",
+			Required: false,
+		},
+		{
+			Name:     "iterator",
+			Required: false,
+		},
+	},
+	Blocks: []hcl.BlockHeaderSchema{
+		{
+			Type: "content",
+		},
+	},
+}

ext/dynblock/functions_hcldec.go

@@ -0,0 +1,48 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
+package dynblock
+
+import (
+	"github.com/terramate-io/hcl/v2"
+	"github.com/terramate-io/hcl/v2/hcldec"
+)
+
+// This is duplicated from ext/dynblock/variables_hcldec.go and modified to suit functions
+
+// FunctionsHCLDec is a wrapper around WalkFunctions that uses the given hcldec
+// specification to automatically drive the recursive walk through nested
+// blocks in the given body.
+//
+// This is a drop-in replacement for hcldec.Functions which is able to treat
+// blocks of type "dynamic" in the same special way that dynblock.Expand would,
+// exposing both the functions referenced in the "for_each" and "labels"
+// arguments and functions used in the nested "content" block.
+func FunctionsHCLDec(body hcl.Body, spec hcldec.Spec) []hcl.Traversal {
+	rootNode := WalkFunctions(body)
+	return walkFunctionsWithHCLDec(rootNode, spec)
+}
+
+// ExpandFunctionsHCLDec is like FunctionsHCLDec but it includes only the
+// minimal set of functions required to call Expand, ignoring functions that
+// are referenced only inside normal block contents. See WalkExpandFunctions
+// for more information.
+func ExpandFunctionsHCLDec(body hcl.Body, spec hcldec.Spec) []hcl.Traversal {
+	rootNode := WalkExpandFunctions(body)
+	return walkFunctionsWithHCLDec(rootNode, spec)
+}
+
+func walkFunctionsWithHCLDec(node WalkFunctionsNode, spec hcldec.Spec) []hcl.Traversal {
+	vars, children := node.Visit(hcldec.ImpliedSchema(spec))
+
+	if len(children) > 0 {
+		childSpecs := hcldec.ChildBlockTypes(spec)
+		for _, child := range children {
+			if childSpec, exists := childSpecs[child.BlockTypeName]; exists {
+				vars = append(vars, walkFunctionsWithHCLDec(child.Node, childSpec)...)
+			}
+		}
+	}
+
+	return vars
+}