Merge pull request rails#50838 from fractaledmind/ar-fix-sqlite-table-structure-parsing

Fix SQLite table definition parsing bug to handle commas in default function definitions

Author: byroot

activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb

@@ -477,11 +477,7 @@ def bind_params_length
         end
 
         def table_structure(table_name)
-          structure = if supports_virtual_columns?
-            internal_exec_query("PRAGMA table_xinfo(#{quote_table_name(table_name)})", "SCHEMA")
-          else
-            internal_exec_query("PRAGMA table_info(#{quote_table_name(table_name)})", "SCHEMA")
-          end
+          structure = table_info(table_name)
           raise ActiveRecord::StatementInvalid.new("Could not find table '#{table_name}'", connection_pool: @pool) if structure.empty?
           table_structure_with_collation(table_name, structure)
         end
@@ -684,7 +680,7 @@ def table_structure_with_collation(table_name, basic_structure)
           auto_increments = {}
           generated_columns = {}
 
-          column_strings = table_structure_sql(table_name)
+          column_strings = table_structure_sql(table_name, basic_structure.map { |column| column["name"] })
 
           if column_strings.any?
             column_strings.each do |column_string|
@@ -719,7 +715,15 @@ def table_structure_with_collation(table_name, basic_structure)
           end
         end
 
-        def table_structure_sql(table_name)
+        UNQUOTED_OPEN_PARENS_REGEX = /\((?![^'"]*['"][^'"]*$)/
+        FINAL_CLOSE_PARENS_REGEX = /\);*\z/
+
+        def table_structure_sql(table_name, column_names = nil)
+          unless column_names
+            column_info = table_info(table_name)
+            column_names = column_info.map { |column| column["name"] }
+          end
+
           sql = <<~SQL
             SELECT sql FROM
               (SELECT * FROM sqlite_master UNION ALL
@@ -729,16 +733,30 @@ def table_structure_sql(table_name)
 
           # Result will have following sample string
           # CREATE TABLE "users" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL,
-          #                       "password_digest" varchar COLLATE "NOCASE");
+          #                       "password_digest" varchar COLLATE "NOCASE",
+          #                       "o_id" integer,
+          #                       CONSTRAINT "fk_rails_78146ddd2e" FOREIGN KEY ("o_id") REFERENCES "os" ("id"));
           result = query_value(sql, "SCHEMA")
 
           return [] unless result
 
           # Splitting with left parentheses and discarding the first part will return all
           # columns separated with comma(,).
-          columns_string = result.split("(", 2).last
+          result.partition(UNQUOTED_OPEN_PARENS_REGEX)
+                .last
+                .sub(FINAL_CLOSE_PARENS_REGEX, "")
+                # column definitions can have a comma in them, so split on commas followed
+                # by a space and a column name in quotes or followed by the keyword CONSTRAINT
+                .split(/,(?=\s(?:CONSTRAINT|"(?:#{Regexp.union(column_names).source})"))/i)
+                .map(&:strip)
+        end
 
-          columns_string.split(",").map(&:strip)
+        def table_info(table_name)
+          if supports_virtual_columns?
+            internal_exec_query("PRAGMA table_xinfo(#{quote_table_name(table_name)})", "SCHEMA")
+          else
+            internal_exec_query("PRAGMA table_info(#{quote_table_name(table_name)})", "SCHEMA")
+          end
         end
 
         def arel_visitor

activerecord/test/cases/adapters/sqlite3/virtual_column_test.rb

@@ -17,6 +17,7 @@ def setup
         t.virtual :upper_name, type: :string, as: "UPPER(name)", stored: true
         t.virtual :lower_name, type: :string, as: "LOWER(name)", stored: false
         t.virtual :octet_name, type: :integer, as: "LENGTH(name)"
+        t.virtual :mutated_name, type: :string, as: "REPLACE(name, 'l', 'L')"
         t.integer :column1
       end
       VirtualColumn.create(name: "Rails", column1: 10)
@@ -58,6 +59,14 @@ def test_implicit_virtual_column
       assert_equal 5, VirtualColumn.take.octet_name
     end
 
+    def test_virtual_column_with_comma_in_definition
+      column = VirtualColumn.columns_hash["mutated_name"]
+      assert_predicate column, :virtual?
+      assert_not_predicate column, :virtual_stored?
+      assert_not_nil column.default_function
+      assert_equal "RaiLs", VirtualColumn.take.mutated_name
+    end
+
     def test_change_table_with_stored_generated_column
       @connection.change_table :virtual_columns do |t|
         t.virtual :decr_column1, type: :integer, as: "column1 - 1", stored: true