Add pragma function capability to sqlite

dialects/sqlite-3-18/src/main/kotlin/app/cash/sqldelight/dialects/sqlite_3_18/grammar/mixins/PragmaFunctionValidatorMixin.kt

@@ -0,0 +1,43 @@
+package app.cash.sqldelight.dialects.sqlite_3_18.grammar.mixins
+
+import com.alecstrong.sql.psi.core.SqlAnnotationHolder
+import com.alecstrong.sql.psi.core.psi.SqlCompositeElement
+import com.alecstrong.sql.psi.core.psi.SqlTypes
+import com.alecstrong.sql.psi.core.psi.impl.SqlPragmaNameImpl
+import com.intellij.lang.ASTNode
+import com.intellij.psi.tree.TokenSet
+
+internal abstract class PragmaFunctionValidatorMixin(node: ASTNode) : SqlPragmaNameImpl(node) {
+    private fun SqlCompositeElement.annotateReservedKeywords(annotationHolder: SqlAnnotationHolder) {
+        children.filterIsInstance<SqlCompositeElement>().forEach {
+            it.annotateReservedKeywords(annotationHolder)
+        }
+        node.getChildren(TokenSet.create(SqlTypes.ID)).forEach {
+            if (it.text !in acceptedKeys) {
+                annotationHolder.createErrorAnnotation(this, "not a valid pragma function")
+            }
+        }
+    }
+    override fun annotate(annotationHolder: SqlAnnotationHolder) {
+        annotateReservedKeywords(annotationHolder)
+        super.annotate(annotationHolder)
+    }
+
+    companion object {
+        // This list is providing the names for all pragma functions that we should support.
+        // For more information please look at the list of pragma https://www.sqlite.org/pragma.html#syntax
+        private val acceptedKeys = setOf(
+                "pragma_application_id",
+                "pragma_cache_size",
+                "pragma_cache_spill",
+                "pragma_compile_options",
+                "pragma_count_changes",
+                "pragma_cell_size_check",
+                "pragma_freelist_count",
+                "pragma_max_page_count",
+                "pragma_page_size",
+                "pragma_page_count",
+                "pragma_user_version",
+        )
+    }
+}

dialects/sqlite-3-18/src/main/kotlin/app/cash/sqldelight/dialects/sqlite_3_18/grammar/sqlite.bnf

@@ -12,9 +12,22 @@
     "static com.alecstrong.sql.psi.core.psi.SqlTypes.DIGIT"
     "static com.alecstrong.sql.psi.core.psi.SqlTypes.DOT"
     "static com.alecstrong.sql.psi.core.psi.SqlTypes.TABLE"
+    "static com.alecstrong.sql.psi.core.psi.SqlTypes.LP"
+    "static com.alecstrong.sql.psi.core.psi.SqlTypes.RP"
+    "static com.alecstrong.sql.psi.core.psi.SqlTypes.SELECT"
+    "static com.alecstrong.sql.psi.core.psi.SqlTypes.DISTINCT"
+    "static com.alecstrong.sql.psi.core.psi.SqlTypes.ALL"
+    "static com.alecstrong.sql.psi.core.psi.SqlTypes.COMMA"
+    "static com.alecstrong.sql.psi.core.psi.SqlTypes.FROM"
+    "static com.alecstrong.sql.psi.core.psi.SqlTypes.WHERE"
+    "static com.alecstrong.sql.psi.core.psi.SqlTypes.HAVING"
+    "static com.alecstrong.sql.psi.core.psi.SqlTypes.VALUES"
+    "static com.alecstrong.sql.psi.core.psi.SqlTypes.FOR"
+    "static com.alecstrong.sql.psi.core.psi.SqlTypes.SEPARATOR"
+    "static com.alecstrong.sql.psi.core.psi.SqlTypes.MULTIPLY"
   ]
 }
-overrides ::= type_name | bind_parameter | alter_table_stmt
+overrides ::= type_name | bind_parameter | alter_table_stmt | select_stmt
 
 type_name ::= text_data_type | blob_data_type | int_data_type | real_data_type {
   extends = "com.alecstrong.sql.psi.core.psi.impl.SqlTypeNameImpl"
@@ -40,3 +53,14 @@ alter_table_stmt ::= ALTER TABLE [ {database_name} DOT ] {table_name} {alter_tab
   pin = 1
   override = true
 }
+
+select_stmt ::= SELECT [ DISTINCT | ALL ] {result_column} ( COMMA {result_column} ) * [ FROM ([ {database_name} DOT ] pragma_function_expr | {join_clause})] [ WHERE <<expr '-1'>> ] [{group_by}] [ HAVING <<expr '-1'>> ] | VALUES {values_expression} ( COMMA {values_expression} ) * {
+  extends = "com.alecstrong.sql.psi.core.psi.impl.SqlSelectStmtImpl"
+  implements = "com.alecstrong.sql.psi.core.psi.SqlSelectStmt"
+  override = true
+  pin = 1
+}
+
+pragma_function_expr ::= {pragma_name} LP [ [ DISTINCT ] <<expr'-1'>> ( ( COMMA | FROM | FOR | SEPARATOR )  <<expr'-1'>> ) * | MULTIPLY ] RP {
+  mixin = "app.cash.sqldelight.dialects.sqlite_3_18.grammar.mixins.PragmaFunctionValidatorMixin"
+}

dialects/sqlite-3-18/src/test/fixtures_sqlite_3_18/pragma-statements/Test.s

@@ -0,0 +1,2 @@
+SELECT * FROM pragma_freelist_count();
+SELECT * FROM pragma_freelist_counter(); -- failure

dialects/sqlite-3-18/src/test/fixtures_sqlite_3_18/pragma-statements/failure.txt

@@ -0,0 +1 @@
+Test.s line 2:14 - not a valid pragma function

dialects/sqlite-3-25/src/main/kotlin/app/cash/sqldelight/dialects/sqlite_3_25/grammar/sqlite.bnf

@@ -54,13 +54,17 @@ result_column ::= ( MULTIPLY
   implements = "com.alecstrong.sql.psi.core.psi.SqlResultColumn"
   override = true
 }
-select_stmt ::= SELECT [ DISTINCT | ALL ] {result_column} ( COMMA {result_column} ) * [ FROM {join_clause} ] [ WHERE <<expr '-1'>> ] [{group_by}] [ HAVING <<expr '-1'>> ] [ WINDOW window_name AS window_defn ( COMMA window_name AS window_defn ) * ] | VALUES {values_expression} ( COMMA {values_expression} ) * {
+select_stmt ::= SELECT [ DISTINCT | ALL ] {result_column} ( COMMA {result_column} ) * [ FROM ([ {database_name} DOT ] pragma_function_expr | {join_clause}) ] [ WHERE <<expr '-1'>> ] [{group_by}] [ HAVING <<expr '-1'>> ] [ WINDOW window_name AS window_defn ( COMMA window_name AS window_defn ) * ] | VALUES {values_expression} ( COMMA {values_expression} ) * {
   extends = "com.alecstrong.sql.psi.core.psi.impl.SqlSelectStmtImpl"
   implements = "com.alecstrong.sql.psi.core.psi.SqlSelectStmt"
   override = true
   pin = 1
 }
 
+pragma_function_expr ::= {pragma_name} LP [ [ DISTINCT ] <<expr'-1'>> ( ( COMMA | FROM | FOR | SEPARATOR )  <<expr'-1'>> ) * | MULTIPLY ] RP {
+  mixin = "app.cash.sqldelight.dialects.sqlite_3_18.grammar.mixins.PragmaNamed"
+}
+
 alter_table_rename_column ::= RENAME [ COLUMN ] {column_name} TO {column_alias} {
   mixin = "app.cash.sqldelight.dialects.sqlite_3_25.grammar.mixins.AlterTableRenameColumnMixin"
   pin = 1
@@ -101,4 +105,4 @@ frame_spec ::= ( 'RANGE' | 'ROWS' | 'GROUPS' )
 
 window_func ::= id
 window_name ::= id
-base_window_name ::= id
+base_window_name ::= id