misc: replace as many user-facing references to River as possible

Replace as many user-facing references to River with "syntax",
"configuration", "Alloy configuration syntax", or "Alloy configuration"
as much as possible.

This is a first pass, and more passes will be needed closer to the 1.0
launch.

internal/flow/internal/controller/node_builtin_component.go

@@ -224,7 +224,7 @@ func (cn *BuiltinComponentNode) NodeID() string { return cn.nodeID }
 // BuiltinComponentNode.
 func (cn *BuiltinComponentNode) UpdateBlock(b *ast.BlockStmt) {
 	if !BlockComponentID(b).Equals(cn.id) {
-		panic("UpdateBlock called with an River block with a different component ID")
+		panic("UpdateBlock called with an block with a different component ID")
 	}
 
 	cn.mut.Lock()
@@ -258,7 +258,7 @@ func (cn *BuiltinComponentNode) evaluate(scope *vm.Scope) error {
 
 	argsPointer := cn.reg.CloneArguments()
 	if err := cn.eval.Evaluate(scope, argsPointer); err != nil {
-		return fmt.Errorf("decoding River: %w", err)
+		return fmt.Errorf("decoding configuration: %w", err)
 	}
 
 	// args is always a pointer to the args type, so we want to deference it since

internal/flow/internal/controller/node_config_argument.go

@@ -53,7 +53,7 @@ func (cn *ArgumentConfigNode) Evaluate(scope *vm.Scope) error {
 
 	var argument argumentBlock
 	if err := cn.eval.Evaluate(scope, &argument); err != nil {
-		return fmt.Errorf("decoding River: %w", err)
+		return fmt.Errorf("decoding configuration: %w", err)
 	}
 
 	cn.defaultValue = argument.Default

internal/flow/internal/controller/node_config_export.go

@@ -50,7 +50,7 @@ func (cn *ExportConfigNode) Evaluate(scope *vm.Scope) error {
 
 	var export exportBlock
 	if err := cn.eval.Evaluate(scope, &export); err != nil {
-		return fmt.Errorf("decoding River: %w", err)
+		return fmt.Errorf("decoding configuration: %w", err)
 	}
 	cn.value = export.Value
 	return nil

internal/flow/internal/controller/node_config_logging.go

@@ -60,7 +60,7 @@ func (cn *LoggingConfigNode) Evaluate(scope *vm.Scope) error {
 	args := logging.DefaultOptions
 	if cn.eval != nil {
 		if err := cn.eval.Evaluate(scope, &args); err != nil {
-			return fmt.Errorf("decoding River: %w", err)
+			return fmt.Errorf("decoding configuration: %w", err)
 		}
 	}
 

internal/flow/internal/controller/node_config_tracing.go

@@ -60,7 +60,7 @@ func (cn *TracingConfigNode) Evaluate(scope *vm.Scope) error {
 	args := tracing.DefaultOptions
 	if cn.eval != nil {
 		if err := cn.eval.Evaluate(scope, &args); err != nil {
-			return fmt.Errorf("decoding River: %w", err)
+			return fmt.Errorf("decoding configuration: %w", err)
 		}
 	}
 

internal/flow/internal/controller/node_custom_component.go

@@ -181,7 +181,7 @@ func (cn *CustomComponentNode) evaluate(evalScope *vm.Scope) error {
 
 	var args map[string]any
 	if err := cn.eval.Evaluate(evalScope, &args); err != nil {
-		return fmt.Errorf("decoding River: %w", err)
+		return fmt.Errorf("decoding configuration: %w", err)
 	}
 
 	cn.args = args

internal/flow/internal/controller/node_service.go

@@ -64,7 +64,7 @@ func (sn *ServiceNode) Block() *ast.BlockStmt {
 // ServiceNode.
 func (sn *ServiceNode) UpdateBlock(b *ast.BlockStmt) {
 	if b != nil && !BlockComponentID(b).Equals([]string{sn.NodeID()}) {
-		panic("UpdateBlock called with a River block with a different block ID")
+		panic("UpdateBlock called with a block with a different block ID")
 	}
 
 	sn.mut.Lock()
@@ -97,7 +97,7 @@ func (sn *ServiceNode) Evaluate(scope *vm.Scope) error {
 	argsPointer := reflect.New(reflect.TypeOf(sn.def.ConfigType)).Interface()
 
 	if err := sn.eval.Evaluate(scope, argsPointer); err != nil {
-		return fmt.Errorf("decoding River: %w", err)
+		return fmt.Errorf("decoding configuration: %w", err)
 	}
 
 	// args is always a pointer to the args type, so we want to deference it

internal/flow/internal/importsource/import_file.go

@@ -59,7 +59,7 @@ func (a *importFileConfigBlock) SetToDefault() {
 func (im *ImportFile) Evaluate(scope *vm.Scope) error {
 	var arguments importFileConfigBlock
 	if err := im.eval.Evaluate(scope, &arguments); err != nil {
-		return fmt.Errorf("decoding River: %w", err)
+		return fmt.Errorf("decoding configuration: %w", err)
 	}
 	if im.fileComponent == nil {
 		var err error

internal/flow/internal/importsource/import_git.go

@@ -74,7 +74,7 @@ func NewImportGit(managedOpts component.Options, eval *vm.Evaluator, onContentCh
 func (im *ImportGit) Evaluate(scope *vm.Scope) error {
 	var arguments GitArguments
 	if err := im.eval.Evaluate(scope, &arguments); err != nil {
-		return fmt.Errorf("decoding River: %w", err)
+		return fmt.Errorf("decoding configuration: %w", err)
 	}
 
 	if reflect.DeepEqual(im.args, arguments) {

internal/flow/internal/importsource/import_http.go

@@ -63,7 +63,7 @@ func (args *HTTPArguments) SetToDefault() {
 func (im *ImportHTTP) Evaluate(scope *vm.Scope) error {
 	var arguments HTTPArguments
 	if err := im.eval.Evaluate(scope, &arguments); err != nil {
-		return fmt.Errorf("decoding River: %w", err)
+		return fmt.Errorf("decoding configuration: %w", err)
 	}
 	if im.managedRemoteHTTP == nil {
 		var err error

internal/flow/internal/importsource/import_string.go

@@ -33,7 +33,7 @@ type importStringConfigBlock struct {
 func (im *ImportString) Evaluate(scope *vm.Scope) error {
 	var arguments importStringConfigBlock
 	if err := im.eval.Evaluate(scope, &arguments); err != nil {
-		return fmt.Errorf("decoding River: %w", err)
+		return fmt.Errorf("decoding configuration: %w", err)
 	}
 
 	if reflect.DeepEqual(im.arguments, arguments) {

internal/flow/module.go

@@ -40,7 +40,7 @@ func newModuleController(o *moduleControllerOptions) controller.ModuleController
 // NewModule creates a new, unstarted Module.
 func (m *moduleController) NewModule(id string, export component.ExportFunc) (component.Module, error) {
 	if id != "" && !scanner.IsValidIdentifier(id) {
-		return nil, fmt.Errorf("module ID %q is not a valid River identifier", id)
+		return nil, fmt.Errorf("module ID %q is not a valid identifier", id)
 	}
 
 	m.mut.Lock()
@@ -63,7 +63,7 @@ func (m *moduleController) NewModule(id string, export component.ExportFunc) (co
 // NewCustomComponent creates a new, unstarted CustomComponent.
 func (m *moduleController) NewCustomComponent(id string, export component.ExportFunc) (controller.CustomComponent, error) {
 	if id != "" && !scanner.IsValidIdentifier(id) {
-		return nil, fmt.Errorf("customComponent ID %q is not a valid River identifier", id)
+		return nil, fmt.Errorf("customComponent ID %q is not a valid identifier", id)
 	}
 
 	m.mut.Lock()

internal/flowmode/cmd_convert.go

@@ -26,9 +26,9 @@ func convertCommand() *cobra.Command {
 
 	cmd := &cobra.Command{
 		Use:   "convert [flags] [file]",
-		Short: "Convert a supported config file to River",
+		Short: "Convert a supported config file to Alloy",
 		Long: `The convert subcommand translates a supported config file to
-a River configuration file.
+an Alloy configuration file.
 
 If the file argument is not supplied or if the file argument is "-", then
 convert will read from stdin.

internal/flowmode/cmd_fmt.go

@@ -21,9 +21,9 @@ func fmtCommand() *cobra.Command {
 
 	cmd := &cobra.Command{
 		Use:   "fmt [flags] file",
-		Short: "Format a River file",
-		Long: `The fmt subcommand applies standard formatting rules to the specified
-River configuration file.
+		Short: "Format a configuration file",
+		Long: `The fmt subcommand applies standard formatting rules to the
+specified configuration file.
 
 If the file argument is not supplied or if the file argument is "-", then fmt will read from stdin.
 

internal/flowmode/cmd_run.go

@@ -68,8 +68,9 @@ func runCommand() *cobra.Command {
 		Long: `The run subcommand runs Grafana Agent Flow in the foreground until an interrupt
 is received.
 
-run must be provided an argument pointing at the River dir/file-path to use. If the
-River dir/file-path wasn't specified, can't be loaded, or contains errors, run will exit
+run must be provided an argument pointing at the Alloy configuration
+dirirectory or file path to use. If the configuration directory or file path
+wasn't specified, can't be loaded, or contains errors, run will exit
 immediately.
 
 If path is a directory, all *.river files in that directory will be combined

internal/service/remotecfg/remotecfg_test.go

@@ -42,7 +42,7 @@ func TestOnDiskCache(t *testing.T) {
 	env.svc.asClient = client
 
 	// Mock client to return an unparseable response.
-	client.getConfigFunc = buildGetConfigHandler("unparseable river config")
+	client.getConfigFunc = buildGetConfigHandler("unparseable config")
 
 	// Write the cache contents, and run the service.
 	err := os.WriteFile(env.svc.dataPath, []byte(cacheContents), 0644)

syntax/ast/walk.go

@@ -66,7 +66,7 @@ func Walk(v Visitor, node Node) {
 	case *ParenExpr:
 		Walk(v, n.Inner)
 	default:
-		panic(fmt.Sprintf("river/ast: unexpected node type %T", n))
+		panic(fmt.Sprintf("syntax/ast: unexpected node type %T", n))
 	}
 
 	v.Visit(nil)

syntax/encoding/riverjson/riverjson.go

@@ -61,7 +61,7 @@ func encodeStructAsBody(rv reflect.Value) jsonBody {
 
 	case reflect.Map:
 		if rv.Type().Key().Kind() != reflect.String {
-			panic("river/encoding/riverjson: unsupported map type; expected map[string]T, got " + rv.Type().String())
+			panic("syntax/encoding/riverjson: unsupported map type; expected map[string]T, got " + rv.Type().String())
 		}
 
 		iter := rv.MapRange()
@@ -76,7 +76,7 @@ func encodeStructAsBody(rv reflect.Value) jsonBody {
 		}
 
 	default:
-		panic(fmt.Sprintf("river/encoding/riverjson: can only encode struct or map[string]T values to bodies, got %s", rv.Kind()))
+		panic(fmt.Sprintf("syntax/encoding/riverjson: can only encode struct or map[string]T values to bodies, got %s", rv.Kind()))
 	}
 
 	return body
@@ -111,7 +111,7 @@ func encodeFieldAsStatements(prefix []string, field rivertags.Field, fieldValue
 			// Iterate over the map and add each element as an attribute into it.
 
 			if fieldValue.Type().Key().Kind() != reflect.String {
-				panic("river/encoding/riverjson: unsupported map type for block; expected map[string]T, got " + fieldValue.Type().String())
+				panic("syntax/encoding/riverjson: unsupported map type for block; expected map[string]T, got " + fieldValue.Type().String())
 			}
 
 			statements := []jsonStatement{}
@@ -182,7 +182,7 @@ func encodeFieldAsStatements(prefix []string, field rivertags.Field, fieldValue
 			return statements
 
 		default:
-			panic(fmt.Sprintf("river/encoding/riverjson: unrecognized enum kind %s", fieldValue.Kind()))
+			panic(fmt.Sprintf("syntax/encoding/riverjson: unrecognized enum kind %s", fieldValue.Kind()))
 		}
 	}
 
@@ -308,6 +308,6 @@ func buildJSONValue(v value.Value) jsonValue {
 		return jsonValue{Type: "capsule", Value: v.Describe()}
 
 	default:
-		panic(fmt.Sprintf("river/encoding/riverjson: unrecognized value type %q", v.Type()))
+		panic(fmt.Sprintf("syntax/encoding/riverjson: unrecognized value type %q", v.Type()))
 	}
 }

syntax/internal/rivertags/rivertags.go

@@ -148,7 +148,7 @@ func (f Field) IsLabel() bool { return f.Flags&FlagLabel != 0 }
 // `river:",label"` tags, which must be strings.
 func Get(ty reflect.Type) []Field {
 	if k := ty.Kind(); k != reflect.Struct {
-		panic(fmt.Sprintf("rivertags: Get requires struct kind, got %s", k))
+		panic(fmt.Sprintf("syntaxtags: Get requires struct kind, got %s", k))
 	}
 
 	var (
@@ -161,7 +161,7 @@ func Get(ty reflect.Type) []Field {
 	for _, field := range reflect.VisibleFields(ty) {
 		// River does not support embedding of fields
 		if field.Anonymous {
-			panic(fmt.Sprintf("river: anonymous fields not supported %s", printPathToField(ty, field.Index)))
+			panic(fmt.Sprintf("syntax: anonymous fields not supported %s", printPathToField(ty, field.Index)))
 		}
 
 		tag, tagged := field.Tag.Lookup("river")
@@ -170,15 +170,15 @@ func Get(ty reflect.Type) []Field {
 		}
 
 		if !field.IsExported() {
-			panic(fmt.Sprintf("river: river tag found on unexported field at %s", printPathToField(ty, field.Index)))
+			panic(fmt.Sprintf("syntax: river tag found on unexported field at %s", printPathToField(ty, field.Index)))
 		}
 
 		options := strings.SplitN(tag, ",", 2)
 		if len(options) == 0 {
-			panic(fmt.Sprintf("river: unsupported empty tag at %s", printPathToField(ty, field.Index)))
+			panic(fmt.Sprintf("syntax: unsupported empty tag at %s", printPathToField(ty, field.Index)))
 		}
 		if len(options) != 2 {
-			panic(fmt.Sprintf("river: field %s tag is missing options", printPathToField(ty, field.Index)))
+			panic(fmt.Sprintf("syntax: field %s tag is missing options", printPathToField(ty, field.Index)))
 		}
 
 		fullName := options[0]
@@ -189,18 +189,18 @@ func Get(ty reflect.Type) []Field {
 		}
 
 		if first, used := usedNames[fullName]; used && fullName != "" {
-			panic(fmt.Sprintf("river: field name %s already used by %s", fullName, printPathToField(ty, first)))
+			panic(fmt.Sprintf("syntax: field name %s already used by %s", fullName, printPathToField(ty, first)))
 		}
 		usedNames[fullName] = tf.Index
 
 		flags, ok := parseFlags(options[1])
 		if !ok {
-			panic(fmt.Sprintf("river: unrecognized river tag format %q at %s", tag, printPathToField(ty, tf.Index)))
+			panic(fmt.Sprintf("syntax: unrecognized river tag format %q at %s", tag, printPathToField(ty, tf.Index)))
 		}
 		tf.Flags = flags
 
 		if len(tf.Name) > 1 && tf.Flags&(FlagBlock|FlagEnum) == 0 {
-			panic(fmt.Sprintf("river: field names with `.` may only be used by blocks or enums (found at %s)", printPathToField(ty, tf.Index)))
+			panic(fmt.Sprintf("syntax: field names with `.` may only be used by blocks or enums (found at %s)", printPathToField(ty, tf.Index)))
 		}
 
 		if tf.Flags&FlagEnum != 0 {
@@ -211,21 +211,21 @@ func Get(ty reflect.Type) []Field {
 
 		if tf.Flags&FlagLabel != 0 {
 			if fullName != "" {
-				panic(fmt.Sprintf("river: label field at %s must not have a name", printPathToField(ty, tf.Index)))
+				panic(fmt.Sprintf("syntax: label field at %s must not have a name", printPathToField(ty, tf.Index)))
 			}
 			if field.Type.Kind() != reflect.String {
-				panic(fmt.Sprintf("river: label field at %s must be a string", printPathToField(ty, tf.Index)))
+				panic(fmt.Sprintf("syntax: label field at %s must be a string", printPathToField(ty, tf.Index)))
 			}
 
 			if usedLabelField != nil {
-				panic(fmt.Sprintf("river: label field already used by %s", printPathToField(ty, tf.Index)))
+				panic(fmt.Sprintf("syntax: label field already used by %s", printPathToField(ty, tf.Index)))
 			}
 			usedLabelField = tf.Index
 		}
 
 		if tf.Flags&FlagSquash != 0 {
 			if fullName != "" {
-				panic(fmt.Sprintf("river: squash field at %s must not have a name", printPathToField(ty, tf.Index)))
+				panic(fmt.Sprintf("syntax: squash field at %s must not have a name", printPathToField(ty, tf.Index)))
 			}
 
 			innerType := deferenceType(field.Type)
@@ -245,14 +245,14 @@ func Get(ty reflect.Type) []Field {
 				}
 
 			default:
-				panic(fmt.Sprintf("rivertags: squash field requires struct, got %s", innerType))
+				panic(fmt.Sprintf("syntaxtags: squash field requires struct, got %s", innerType))
 			}
 
 			continue
 		}
 
 		if fullName == "" && tf.Flags&(FlagLabel|FlagSquash) == 0 /* (e.g., *not* a label or squash) */ {
-			panic(fmt.Sprintf("river: non-empty field name required at %s", printPathToField(ty, tf.Index)))
+			panic(fmt.Sprintf("syntaxtags: non-empty field name required at %s", printPathToField(ty, tf.Index)))
 		}
 
 		fields = append(fields, tf)

syntax/token/builder/builder.go

@@ -174,7 +174,7 @@ func (b *Body) encodeFields(rv reflect.Value) {
 		rv = rv.Elem()
 	}
 	if rv.Kind() != reflect.Struct {
-		panic(fmt.Sprintf("river/token/builder: can only encode struct values to bodies, got %s", rv.Type()))
+		panic(fmt.Sprintf("syntax/token/builder: can only encode struct values to bodies, got %s", rv.Type()))
 	}
 
 	fields := rivertags.Get(rv.Type())
@@ -223,7 +223,7 @@ func (b *Body) encodeField(prefix []string, field rivertags.Field, fieldValue re
 		case fieldValue.Kind() == reflect.Map:
 			// Iterate over the map and add each element as an attribute into it.
 			if fieldValue.Type().Key().Kind() != reflect.String {
-				panic("river/token/builder: unsupported map type for block; expected map[string]T, got " + fieldValue.Type().String())
+				panic("syntax/token/builder: unsupported map type for block; expected map[string]T, got " + fieldValue.Type().String())
 			}
 
 			inner := NewBlock(fullName, "")
@@ -267,7 +267,7 @@ func (b *Body) encodeField(prefix []string, field rivertags.Field, fieldValue re
 			}
 
 		default:
-			panic(fmt.Sprintf("river/token/builder: unrecognized enum kind %s", fieldValue.Kind()))
+			panic(fmt.Sprintf("syntax/token/builder: unrecognized enum kind %s", fieldValue.Kind()))
 		}
 	}
 }

syntax/vm/op_binary.go

@@ -204,7 +204,7 @@ func evalBinop(lhs value.Value, op token.Token, rhs value.Value) (value.Value, e
 		}
 	}
 
-	panic("river/vm: unreachable")
+	panic("syntax/vm: unreachable")
 }
 
 // tryUnwrapOptionalSecret accepts a value and, if it is a
@@ -294,7 +294,7 @@ func valuesEqual(lhs value.Value, rhs value.Value) bool {
 		return reflect.DeepEqual(lhs.Interface(), rhs.Interface())
 	}
 
-	panic("river/vm: unreachable")
+	panic("syntax/vm: unreachable")
 }
 
 // binopAllowedTypes maps what type of values are permitted for a specific
@@ -322,7 +322,7 @@ var binopAllowedTypes = map[token.Token][]value.Type{
 func acceptableBinopType(val value.Value, op token.Token) bool {
 	allowed, ok := binopAllowedTypes[op]
 	if !ok {
-		panic("river/vm: unexpected binop type")
+		panic("syntax/vm: unexpected binop type")
 	}
 
 	actualType := val.Type()

syntax/vm/op_unary.go

@@ -29,5 +29,5 @@ func evalUnaryOp(op token.Token, val value.Value) (value.Value, error) {
 		}
 	}
 
-	panic("river/vm: unreachable")
+	panic("syntax/vm: unreachable")
 }