Oh, this method is completely broken since the fix of bug 671417... HTMLEditor::GetNumberOfCellsInRow() returned non-false before the fix. So, the callers continued to handling something. However, after the fix, it returns 0 and all callers check whether the result is 1 or not. I.e., before the fix, the callers always treated as there were 2 or more columns since nsresult values are not 1. I'll fix this bug for writing automated tests.

This add automated tests for nsITableEditor.deleteTableColumn(). However, this contains some fixes of existing code since with those bugs, the test isn't passed even in the simplest case.

nsITableEditor::DeleteTableColumn() is an XPCOM method but used internally. So, it should be implemented with non-virtual method and internal users should use it. Note that this changes only one thing. This moves |AutoTopLevelEditSubActionNotifier maybeTopLevelEditSubAction(...| from below DeleteTableElementAndChildrenWithTransaction() to above it. I.e., DeleteTableElementAndChildrenWithTransaction() works under EditSubAction::eDeleteNode as the top level sub-action now. This is same as DeleteSelectedTableRowsWithTransaction(). Therefore, the difference with it when it removes <table> is now fixed.

This patch renames HTMLEditor::DeleteColumn() to HTMLEditor::DeleteTableColumnWithTransaction() and cleans up its implementation.

Makoto-san: I guess that this bug's request was dropped from your todo list. All other review requests depend on this, so, I'd like you to review this first.

Comment on attachment 9009322 [details] Bug 1484121 - part 0: Add automated tests for nsITableEditor.deleteTableColumn() Makoto Kato [:m_kato] has approved the revision.

Comment on attachment 9009323 [details] Bug 1484121 - part 1: Create HTMLEditor::DeleteSelectedTableColumnsWithTransaction() for internal use of nsITableEditor::DeleteTableColumn() Makoto Kato [:m_kato] has approved the revision.

Comment on attachment 9009324 [details] Bug 1484121 - part 2: Clean up HTMLEditor::DeleteColumn() Makoto Kato [:m_kato] has approved the revision.

Pushed by masayuki@d-toybox.com: https://hg.mozilla.org/integration/autoland/rev/d3f152e4c6cf part 0: Add automated tests for nsITableEditor.deleteTableColumn() r=m_kato https://hg.mozilla.org/integration/autoland/rev/d2025ca568f7 part 1: Create HTMLEditor::DeleteSelectedTableColumnsWithTransaction() for internal use of nsITableEditor::DeleteTableColumn() r=m_kato https://hg.mozilla.org/integration/autoland/rev/a0f7c46838a0 part 2: Clean up HTMLEditor::DeleteColumn() r=m_kato

https://hg.mozilla.org/mozilla-central/rev/d3f152e4c6cf https://hg.mozilla.org/mozilla-central/rev/d2025ca568f7 https://hg.mozilla.org/mozilla-central/rev/a0f7c46838a0