SQLite dropColumn doesn't work for last column

[ismyrnow]

The logic for dropping a column prevents the last column in a table from being dropped.

var a = this.formatter.wrap(column) + ' ' + currentCol.type + ', ';

// createTable.sql: CREATE TABLE... "some_col" varchar(255), "last_col" varchar(255))
// a: "last_col" varchar(255) ,

if (createTable.sql.indexOf(a) === -1) {
  throw new Error('Unable to find the column to change');
}

The comma after the column definition prevents it from matching the last column.

Here is a link to the code with the above snippet: https://github.com/tgriesser/knex/blob/master/lib/dialects/sqlite3/schema/ddl.js#L150

[ismyrnow]

I looked into adding a test (there isn't one for dropColumn or renameColumn), but all of the sqlite3 tests just verify the SchemaBuilder sql output. The dropColumn function opens a transaction and copies data to a different table, which explains why there isn't currently a test for it.

I'm unsure how to write a test for a function like that.

[mabuzer]

Replacing

if (createTable.sql.indexOf(a) === -1) {
  throw new Error('Unable to find the column to change');
}

With the following snippt fix it.

 if (createTable.sql.indexOf(a) === -1) {
          var a1 = a.substring(0, a.length - 2);
          if(createTable.sql.indexOf(a1) === -1) {
              throw new Error('Unable to find the column to change');
          } else {
              a = ', ' + a1;
         }
  }

[bendrucker]

Thanks @mabuzer. I'll look at getting tests against this behavior.

[morungos]

I just stumbled on this one too. Fortunately, it only affects rolling back my migrations, which hopefully I won't have to do for a while. Can I help?

[bendrucker]

A tested PR is very welcome