Code correction

A computer program, stored on a non-transitory computer readable medium, the computer program which, when executed by one or more processors of a data processing apparatus, causes the data processing apparatus to:

• provide code representing a plurality of data processing elements of an executable data transformer, one or more of the data processing elements being configured to receive one or more datasets and to produce one or more transformed datasets;
• execute a sub-portion of the code up to an inserted breakpoint and display a first result of the executed code sub-portion up to the breakpoint on one or more datasets in a first portion of a user interface;
• receive test code in a second portion of the user interface and executing the test code to apply a transformation on the one or more data sets transformed by the code sub-portion up to the breakpoint to generate an updated result of a test transformation in the first portion, wherein the test code is executed in isolation with respect to the first result;
• insert the test code received in the second portion to the code of the data transformer, responsive to user selection, the test code being inserted after the sub-portion of the code;
• display in a third portion of the user interface the provided code representing the plurality of data processing elements of an executable data transformer, and receiving insertion of the breakpoint by placement of a breakpoint graphic adjacent a line of said code;
• and
• displaying a notification in the event that the breakpoint is moved without insertion of the test code;
• wherein the third portion of the user interface is configure to prevent user modification of said provided code other than by insertion of the test code, and
• wherein the test code comprises one or more commands, wherein inserting the test code to the code of the data transformer further includes inserting each of the one or more commands of the test code.

Apparatus comprising one or more processors or special-purpose computing hardware operable to:

• provide code representing a plurality of data processing elements of an executable data transformer, one or more of the data processing elements being configured to receive one or more datasets and to produce one or more transformed datasets;
• execute a sub-portion of the code up to an inserted breakpoint and display a first result of the executed code sub-portion up to the breakpoint on one or more datasets in a first portion of a user interface;
• receive test code in a second portion of the user interface and execute the test code to apply a transformation on the one or more data sets transformed by the code sub-portion up to the breakpoint to generate an updated result of a test transformation in the first portion, wherein the test code is executed in isolation with respect to the first result;
• insert the test code received in the second portion to the code of the data transformer, responsive to user selection, the test code being inserted after the sub-portion of the code;
• display in a third portion of the user interface the provided code representing the plurality of data processing elements of an executable data transformer, and receiving insertion of the breakpoint by placement of a breakpoint graphic adjacent a line of said code;
• and
• displaying a notification in the event that the breakpoint is moved without insertion of the test code;
• wherein the third portion of the user interface is configure to prevent user modification of said provided code other than by insertion of the test code, and
• wherein the test code comprises one or more commands, wherein inserting the test code to the code of the data transformer further includes inserting each of the one or more commands of the test code.