internal/rosa/azalea: pass through source ident

For source handle special case.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/rosa/azalea/evaluate.go

@@ -142,10 +142,13 @@ var (
 	IdentInputs = unique.Make(Ident("inputs"))
 	// IdentRuntime has the same semantics as [IdentInputs].
 	IdentRuntime = unique.Make(Ident("runtime"))
+	// IdentSource is a special argument in a package declaration where an
+	// assignment of a [Val] with a single [Ident] passes through the evaluator.
+	IdentSource = unique.Make(Ident("source"))
 
-	// ErrInvalidInputs is panicked for an [IdentInputs] argument to [PF]
-	// sharing its value or set for R.
-	ErrInvalidInputs = errors.New("inputs must not be common or bound to scope")
+	// ErrInvalidSpecial is panicked for a special [PF] argument sharing its
+	// value or set for R.
+	ErrInvalidSpecial = errors.New("special must not be common or bound to scope")
 )
 
 // evaluateAny implements [Evaluate].
@@ -291,7 +294,7 @@ func evaluateAny(d PF, s []Frame, expr, rp any) bool {
 				} {
 					if slices.Contains(names, special) {
 						if len(names) != 1 || len(arg.V) != 1 || arg.R {
-							panic(ErrInvalidInputs)
+							panic(ErrInvalidSpecial)
 						}
 						farg.K = names[0]
 						if err := storeE(&farg.V, arg.V[0]); err != nil {
@@ -301,6 +304,20 @@ func evaluateAny(d PF, s []Frame, expr, rp any) bool {
 						continue args
 					}
 				}
+
+				if slices.Contains(names, IdentSource) {
+					if len(names) != 1 || len(arg.V) != 1 || arg.R {
+						panic(ErrInvalidSpecial)
+					}
+					if _, ok = arg.V[0].(Ident); ok {
+						farg.K = names[0]
+						if err := storeE(&farg.V, arg.V[0]); err != nil {
+							panic(err)
+						}
+						fargs = append(fargs, farg)
+						continue args
+					}
+				}
 			}
 
 			if !evaluateAny(d, s, arg.V, &farg.V) {

internal/rosa/azalea/evaluate_test.go

@@ -32,7 +32,7 @@ func TestEvaluate(t *testing.T) {
 		name string
 		data string
 		s    []Frame
-		want string
+		want any
 		err  error
 	}{
 		{"apply unset", `f { v = unset; }`, makeStackCheck(func(
@@ -110,7 +110,7 @@ func TestEvaluate(t *testing.T) {
 					}, V: Val{Array(nil)}},
 				},
 			},
-			Err: ErrInvalidInputs,
+			Err: ErrInvalidSpecial,
 		}},
 
 		{"bound inputs", `package name { inputs* = []; }`, nil, "", EvaluationError{
@@ -122,7 +122,7 @@ func TestEvaluate(t *testing.T) {
 					{K: []Ident{"inputs"}, V: Val{Array(nil)}, R: true},
 				},
 			},
-			Err: ErrInvalidInputs,
+			Err: ErrInvalidSpecial,
 		}},
 
 		{"bound runtime", `package name { runtime* = []; }`, nil, "", EvaluationError{
@@ -134,7 +134,7 @@ func TestEvaluate(t *testing.T) {
 					{K: []Ident{"runtime"}, V: Val{Array(nil)}, R: true},
 				},
 			},
-			Err: ErrInvalidInputs,
+			Err: ErrInvalidSpecial,
 		}},
 
 		{"concat inputs", `package name { inputs = ""+""; }`, nil, "", EvaluationError{
@@ -146,8 +146,24 @@ func TestEvaluate(t *testing.T) {
 					{K: []Ident{"inputs"}, V: Val{String(""), String("")}},
 				},
 			},
-			Err: ErrInvalidInputs,
+			Err: ErrInvalidSpecial,
 		}},
+
+		{"concat source", `package name { source = ""+""; }`, nil, "", EvaluationError{
+			Expr: Func{
+				Ident:   Ident("name"),
+				Package: true,
+
+				Args: []Arg{
+					{K: []Ident{"source"}, V: Val{String(""), String("")}},
+				},
+			},
+			Err: ErrInvalidSpecial,
+		}},
+
+		{"source handle", `package name { source = name; }`, nil, FArgs{
+			{K: unique.Make(Ident("source")), V: Ident("name")},
+		}, nil},
 	}
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
@@ -161,12 +177,23 @@ func TestEvaluate(t *testing.T) {
 			} else {
 				expr = e[0].(Func)
 			}
-			r, set, err := Evaluate[string](nil, tc.s, expr)
+			const rPackage = "\xff\xff\xff\xff"
+			r, set, err := Evaluate[string](func(
+				name Ident,
+				args FArgs,
+			) (v any, set bool, err error) {
+				v = rPackage
+				if !reflect.DeepEqual(args, tc.want) {
+					err = fmt.Errorf("%#v, want %#v", args, tc.want)
+				}
+				set = true
+				return
+			}, tc.s, expr)
 			if set != (err == nil) {
 				t.Error("Evaluate: unexpected unset")
 			}
 
-			if r != tc.want {
+			if r != rPackage && r != tc.want {
 				t.Errorf("Evaluate: %q, want %q", r, tc.want)
 			}
 

internal/rosa/state.go

@@ -789,6 +789,13 @@ func (ctx *evalContext) pf(
 	case deferredGit:
 		source = ctx.t.newTagRemote(p.url, p.tag, p.checksum)
 
+	case azalea.Ident:
+		var _meta *Metadata
+		_meta, source = ctx.t.Load(H(string(p)))
+		if meta.Version == "" {
+			meta.Version = _meta.Version
+		}
+
 	default:
 		panic(azalea.TypeError{
 			Concrete: reflect.TypeOf(sourceA),