Optionally disable verification code (#173)

docs/content/en/docs/Advanced Features/builder_options.md

@@ -34,4 +34,8 @@ At the moment, moor supports these options:
    methods returning a `Stream` or a `Future`. As the `Selectable` class contains its own methods
    to convert it to a `Stream` and `Future`, the two later methods only exist for backwards
    compatibility. When this flag is enabled, moor won't write them at all. This will be the only
-   option in moor 3.0
+   option in moor 3.0
+* `skip_verification_code`: Generated tables contain a significant chunk of code to verify integrity
+  of inserted data and report detailed errors when the integrity is violated. If you're only using
+  inserts with SQL, or don't need this functionality, enabling this flag can help to reduce the amount
+  generated code.

moor/lib/src/runtime/structure/error_handling.dart

@@ -34,11 +34,19 @@ class VerificationResult {
 
 /// Used internally by moor for integrity checks.
 class VerificationContext {
-  final Map<VerificationMeta, VerificationResult> _errors = {};
+  final Map<VerificationMeta, VerificationResult> _errors;
 
   /// Used internally by moor
   bool get dataValid => _errors.isEmpty;
 
+  /// Creates a verification context, which stores the individual integrity
+  /// check results. Used by generated code.
+  VerificationContext() : _errors = {};
+
+  /// Constructs a verification context that can't be used to report error. This
+  /// is used internally by moor if integrity checks have been disabled.
+  const VerificationContext.notEnabled() : _errors = const {};
+
   /// Used internally by moor when inserting
   void handle(VerificationMeta meta, VerificationResult result) {
     if (!result.success) {

moor/lib/src/runtime/structure/table_info.dart

@@ -45,7 +45,11 @@ mixin TableInfo<TableDsl extends Table, D extends DataClass> on Table {
   /// Validates that the given entity can be inserted into this table, meaning
   /// that it respects all constraints (nullability, text length, etc.).
   VerificationContext validateIntegrity(covariant UpdateCompanion<D> instance,
-      {bool isInserting = false});
+      {bool isInserting = false}) {
+    // default behavior when users chose to not verify the integrity (build time
+    // option)
+    return const VerificationContext.notEnabled();
+  }
 
   /// Maps the given update companion to a [Map] that can be inserted into sql.
   /// The keys should represent the column name in sql, the values the

moor_generator/lib/src/backends/build/options.dart

@@ -4,9 +4,13 @@ class MoorOptions {
   final bool generateFromJsonStringConstructor;
   final bool overrideHashAndEqualsInResultSets;
   final bool compactQueryMethods;
+  final bool skipVerificationCode;
 
-  MoorOptions(this.generateFromJsonStringConstructor,
-      this.overrideHashAndEqualsInResultSets, this.compactQueryMethods);
+  MoorOptions(
+      this.generateFromJsonStringConstructor,
+      this.overrideHashAndEqualsInResultSets,
+      this.compactQueryMethods,
+      this.skipVerificationCode);
 
   factory MoorOptions.fromBuilder(Map<String, dynamic> config) {
     final writeFromString =
@@ -18,12 +22,16 @@ class MoorOptions {
     final compactQueryMethods =
         config['compact_query_methods'] as bool ?? false;
 
-    return MoorOptions(
-        writeFromString, overrideInResultSets, compactQueryMethods);
+    final skipVerificationCode =
+        config['skip_verification_code'] as bool ?? false;
+
+    return MoorOptions(writeFromString, overrideInResultSets,
+        compactQueryMethods, skipVerificationCode);
   }
 
   const MoorOptions.defaults()
       : generateFromJsonStringConstructor = false,
         overrideHashAndEqualsInResultSets = false,
-        compactQueryMethods = false;
+        compactQueryMethods = false,
+        skipVerificationCode = false;
 }

moor_generator/lib/src/writer/tables/table_writer.dart

@@ -192,12 +192,16 @@ class TableWriter {
 
   void _writeColumnVerificationMeta(SpecifiedColumn column) {
     // final VerificationMeta _targetDateMeta = const VerificationMeta('targetDate');
-    _buffer
-      ..write('final VerificationMeta ${_fieldNameForColumnMeta(column)} = ')
-      ..write("const VerificationMeta('${column.dartGetterName}');\n");
+    if (!scope.writer.options.skipVerificationCode) {
+      _buffer
+        ..write('final VerificationMeta ${_fieldNameForColumnMeta(column)} = ')
+        ..write("const VerificationMeta('${column.dartGetterName}');\n");
+    }
   }
 
   void _writeValidityCheckMethod() {
+    if (scope.writer.options.skipVerificationCode) return;
+
     _buffer
       ..write('@override\nVerificationContext validateIntegrity'
           '(${table.updateCompanionName} d, {bool isInserting = false}) {\n')