feat: add SHOW FEATURES command with version registry queries

Implements SHOW FEATURES grammar, AST, visitor, and executor:
- SHOW FEATURES [IN area] — list features for connected project version
- SHOW FEATURES FOR VERSION x.y — query any version without a project
- SHOW FEATURES ADDED SINCE x.y — show what's new since a given version

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: ako

cmd/mxcli/lsp_completions_gen.go

@@ -207,6 +207,23 @@ func (t ShowObjectType) String() string {
 	}
 }
 
+// ShowFeaturesStmt represents SHOW FEATURES commands against the version registry.
+type ShowFeaturesStmt struct {
+	// InArea filters by feature area (e.g., "domain_model", "microflows").
+	// Empty means show all areas.
+	InArea string
+
+	// ForVersion queries features for a specific version (SHOW FEATURES FOR VERSION x.y).
+	// Empty means use the connected project's version.
+	ForVersion string
+
+	// AddedSince shows features added after this version (SHOW FEATURES ADDED SINCE x.y).
+	// Empty means show all features (not just new ones).
+	AddedSince string
+}
+
+func (s *ShowFeaturesStmt) isStatement() {}
+
 // SelectStmt represents a SELECT query against catalog tables.
 type SelectStmt struct {
 	Query string // The raw SQL query

mdl/ast/ast_query.go

@@ -0,0 +1,151 @@
+// SPDX-License-Identifier: Apache-2.0
+
+package executor
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/mendixlabs/mxcli/mdl/ast"
+	"github.com/mendixlabs/mxcli/sdk/versions"
+)
+
+// execShowFeatures handles SHOW FEATURES, SHOW FEATURES FOR VERSION, and
+// SHOW FEATURES ADDED SINCE commands.
+func (e *Executor) execShowFeatures(s *ast.ShowFeaturesStmt) error {
+	reg, err := versions.Load()
+	if err != nil {
+		return fmt.Errorf("failed to load version registry: %w", err)
+	}
+
+	// Determine the project version to use.
+	var pv versions.SemVer
+
+	switch {
+	case s.AddedSince != "":
+		// SHOW FEATURES ADDED SINCE x.y
+		sinceV, err := versions.ParseSemVer(s.AddedSince)
+		if err != nil {
+			return fmt.Errorf("invalid version %q: %w", s.AddedSince, err)
+		}
+		return e.showFeaturesAddedSince(reg, sinceV)
+
+	case s.ForVersion != "":
+		// SHOW FEATURES FOR VERSION x.y — no project connection needed
+		pv, err = versions.ParseSemVer(s.ForVersion)
+		if err != nil {
+			return fmt.Errorf("invalid version %q: %w", s.ForVersion, err)
+		}
+
+	default:
+		// SHOW FEATURES [IN area] — requires project connection
+		if e.reader == nil {
+			return fmt.Errorf("not connected to a project\n  hint: use SHOW FEATURES FOR VERSION x.y without a project connection")
+		}
+		rpv := e.reader.ProjectVersion()
+		pv = versions.SemVer{Major: rpv.MajorVersion, Minor: rpv.MinorVersion, Patch: rpv.PatchVersion}
+	}
+
+	if s.InArea != "" {
+		return e.showFeaturesInArea(reg, pv, s.InArea)
+	}
+	return e.showFeaturesAll(reg, pv)
+}
+
+func (e *Executor) showFeaturesAll(reg *versions.Registry, pv versions.SemVer) error {
+	features := reg.FeaturesForVersion(pv)
+	if len(features) == 0 {
+		fmt.Fprintf(e.output, "No features found for version %s\n", pv)
+		return nil
+	}
+
+	fmt.Fprintf(e.output, "Features for Mendix %s:\n\n", pv)
+	fmt.Fprintf(e.output, "| %-30s | %-9s | %-8s | %s |\n", "Feature", "Available", "Since", "Notes")
+	fmt.Fprintf(e.output, "|%s|%s|%s|%s|\n",
+		strings.Repeat("-", 32), strings.Repeat("-", 11), strings.Repeat("-", 10), strings.Repeat("-", 40))
+
+	available, unavailable := 0, 0
+	for _, f := range features {
+		avail := "Yes"
+		if !f.Available {
+			avail = "No"
+			unavailable++
+		} else {
+			available++
+		}
+		notes := f.Notes
+		if !f.Available && f.Workaround != nil {
+			notes = f.Workaround.Description
+		}
+		if len(notes) > 38 {
+			notes = notes[:35] + "..."
+		}
+		fmt.Fprintf(e.output, "| %-30s | %-9s | %-8s | %-38s |\n",
+			f.DisplayName(), avail, f.MinVersion, notes)
+	}
+
+	fmt.Fprintf(e.output, "\n(%d available, %d not available in %s)\n", available, unavailable, pv)
+	return nil
+}
+
+func (e *Executor) showFeaturesInArea(reg *versions.Registry, pv versions.SemVer, area string) error {
+	features := reg.FeaturesInArea(area, pv)
+	if len(features) == 0 {
+		// Check if the area exists at all.
+		areas := reg.Areas()
+		fmt.Fprintf(e.output, "No features found in area %q for version %s\n", area, pv)
+		fmt.Fprintf(e.output, "Available areas: %s\n", strings.Join(areas, ", "))
+		return nil
+	}
+
+	fmt.Fprintf(e.output, "Features in %s for Mendix %s:\n\n", area, pv)
+	fmt.Fprintf(e.output, "| %-30s | %-9s | %-8s | %s |\n", "Feature", "Available", "Since", "Notes")
+	fmt.Fprintf(e.output, "|%s|%s|%s|%s|\n",
+		strings.Repeat("-", 32), strings.Repeat("-", 11), strings.Repeat("-", 10), strings.Repeat("-", 40))
+
+	for _, f := range features {
+		avail := "Yes"
+		if !f.Available {
+			avail = "No"
+		}
+		notes := f.Notes
+		if !f.Available && f.Workaround != nil {
+			notes = f.Workaround.Description
+		}
+		if len(notes) > 38 {
+			notes = notes[:35] + "..."
+		}
+		fmt.Fprintf(e.output, "| %-30s | %-9s | %-8s | %-38s |\n",
+			f.DisplayName(), avail, f.MinVersion, notes)
+	}
+
+	return nil
+}
+
+func (e *Executor) showFeaturesAddedSince(reg *versions.Registry, sinceV versions.SemVer) error {
+	added := reg.FeaturesAddedSince(sinceV)
+	if len(added) == 0 {
+		fmt.Fprintf(e.output, "No new features found since %s\n", sinceV)
+		return nil
+	}
+
+	fmt.Fprintf(e.output, "Features added since Mendix %s:\n\n", sinceV)
+	fmt.Fprintf(e.output, "| %-30s | %-12s | %-10s | %s |\n", "Feature", "Area", "Since", "Notes")
+	fmt.Fprintf(e.output, "|%s|%s|%s|%s|\n",
+		strings.Repeat("-", 32), strings.Repeat("-", 14), strings.Repeat("-", 12), strings.Repeat("-", 40))
+
+	for _, f := range added {
+		notes := f.Notes
+		if f.MDL != "" && notes == "" {
+			notes = f.MDL
+		}
+		if len(notes) > 38 {
+			notes = notes[:35] + "..."
+		}
+		fmt.Fprintf(e.output, "| %-30s | %-12s | %-10s | %-38s |\n",
+			f.DisplayName(), f.Area, f.MinVersion, notes)
+	}
+
+	fmt.Fprintf(e.output, "\n(%d features added since %s)\n", len(added), sinceV)
+	return nil
+}

mdl/executor/cmd_features.go

@@ -329,6 +329,8 @@ func (e *Executor) executeInner(stmt ast.Statement) error {
 	// Query statements
 	case *ast.ShowStmt:
 		return e.execShow(s)
+	case *ast.ShowFeaturesStmt:
+		return e.execShowFeatures(s)
 	case *ast.ShowWidgetsStmt:
 		return e.execShowWidgets(s)
 	case *ast.UpdateWidgetsStmt:

mdl/executor/executor.go

@@ -576,6 +576,14 @@ SUBSCRIBE: S U B S C R I B E;
 SETTINGS: S E T T I N G S;
 CONFIGURATION: C O N F I G U R A T I O N;
 
+// =============================================================================
+// VERSION FEATURE REGISTRY KEYWORDS
+// =============================================================================
+
+FEATURES: F E A T U R E S;
+ADDED: A D D E D;
+SINCE: S I N C E;
+
 // =============================================================================
 // SECURITY KEYWORDS
 // =============================================================================

mdl/grammar/MDLLexer.g4

@@ -2540,6 +2540,9 @@ showStatement
     | SHOW REST CLIENTS (IN (qualifiedName | IDENTIFIER))?           // SHOW REST CLIENTS [IN module]
     | SHOW PUBLISHED REST SERVICES (IN (qualifiedName | IDENTIFIER))? // SHOW PUBLISHED REST SERVICES [IN module]
     | SHOW LANGUAGES                                                 // SHOW LANGUAGES
+    | SHOW FEATURES (IN IDENTIFIER)?                                 // SHOW FEATURES [IN area]
+    | SHOW FEATURES FOR VERSION NUMBER_LITERAL                       // SHOW FEATURES FOR VERSION 10.24
+    | SHOW FEATURES ADDED SINCE NUMBER_LITERAL                       // SHOW FEATURES ADDED SINCE 10.24
     ;
 
 /**