Register ClickHouse engine in compiler

Add engine registration in compiler pipeline and configuration schema.
Enables compiler to recognize and process ClickHouse engine configurations.

Author: mgilbir

internal/compiler/engine.go

@@ -7,15 +7,19 @@ import (
 	"github.com/sqlc-dev/sqlc/internal/analyzer"
 	"github.com/sqlc-dev/sqlc/internal/config"
 	"github.com/sqlc-dev/sqlc/internal/dbmanager"
+	"github.com/sqlc-dev/sqlc/internal/engine/clickhouse"
 	"github.com/sqlc-dev/sqlc/internal/engine/dolphin"
 	"github.com/sqlc-dev/sqlc/internal/engine/postgresql"
 	pganalyze "github.com/sqlc-dev/sqlc/internal/engine/postgresql/analyzer"
 	"github.com/sqlc-dev/sqlc/internal/engine/sqlite"
 	sqliteanalyze "github.com/sqlc-dev/sqlc/internal/engine/sqlite/analyzer"
 	"github.com/sqlc-dev/sqlc/internal/opts"
+	"github.com/sqlc-dev/sqlc/internal/sql/ast"
 	"github.com/sqlc-dev/sqlc/internal/sql/catalog"
 )
 
+type ResolveTypeFunc func(call *ast.FuncCall, fun *catalog.Function, resolve func(n ast.Node) (*catalog.Column, error)) *ast.TypeName
+
 type Compiler struct {
 	conf     config.SQL
 	combo    config.CombinedSettings
@@ -26,7 +30,8 @@ type Compiler struct {
 	client   dbmanager.Client
 	selector selector
 
-	schema []string
+	schema       []string
+	TypeResolver ResolveTypeFunc
 }
 
 func NewCompiler(conf config.SQL, combo config.CombinedSettings) (*Compiler, error) {
@@ -38,6 +43,11 @@ func NewCompiler(conf config.SQL, combo config.CombinedSettings) (*Compiler, err
 	}
 
 	switch conf.Engine {
+	case config.EngineClickHouse:
+		c.parser = clickhouse.NewParser()
+		c.catalog = clickhouse.NewCatalog()
+		c.selector = newDefaultSelector()
+		c.TypeResolver = clickhouse.TypeResolver
 	case config.EngineSQLite:
 		c.parser = sqlite.NewParser()
 		c.catalog = sqlite.NewCatalog()
@@ -79,7 +89,15 @@ func (c *Compiler) Catalog() *catalog.Catalog {
 }
 
 func (c *Compiler) ParseCatalog(schema []string) error {
-	return c.parseCatalog(schema)
+	err := c.parseCatalog(schema)
+	if err == nil && c.conf.Engine == config.EngineClickHouse {
+		// Set the catalog on the ClickHouse parser so it can register
+		// context-dependent functions during query parsing
+		if chParser, ok := c.parser.(*clickhouse.Parser); ok {
+			chParser.Catalog = c.catalog
+		}
+	}
+	return err
 }
 
 func (c *Compiler) ParseQueries(queries []string, o opts.Parser) error {

internal/config/config.go

@@ -51,6 +51,7 @@ func (p *Paths) UnmarshalYAML(unmarshal func(interface{}) error) error {
 }
 
 const (
+	EngineClickHouse Engine = "clickhouse"
 	EngineMySQL      Engine = "mysql"
 	EnginePostgreSQL Engine = "postgresql"
 	EngineSQLite     Engine = "sqlite"

internal/config/v_one.json

@@ -33,6 +33,7 @@
                 "properties": {
                     "engine": {
                         "enum": [
+                            "clickhouse",
                             "postgresql",
                             "mysql",
                             "sqlite"
@@ -192,6 +193,7 @@
                                 },
                                 "engine": {
                                     "enum": [
+                                        "clickhouse",
                                         "postgresql",
                                         "mysql",
                                         "sqlite"
@@ -300,6 +302,7 @@
                     },
                     "engine": {
                         "enum": [
+                            "clickhouse",
                             "postgresql",
                             "mysql",
                             "sqlite"

internal/config/v_two.json

@@ -36,6 +36,7 @@
                     },
                     "engine": {
                         "enum": [
+                            "clickhouse",
                             "postgresql",
                             "mysql",
                             "sqlite"
@@ -201,6 +202,7 @@
                                                 },
                                                 "engine": {
                                                     "enum": [
+                                                        "clickhouse",
                                                         "postgresql",
                                                         "mysql",
                                                         "sqlite"
@@ -358,6 +360,7 @@
                                     },
                                     "engine": {
                                         "enum": [
+                                            "clickhouse",
                                             "postgresql",
                                             "mysql",
                                             "sqlite"