lots more tests

I've been adding diligently to manual_tests but not actually
_performing_ any manual tests before releases. They were just a todo
list of automated tests to write, and long out of date. Now the list is
up to date and much shorter.

manual_tests

@@ -5,47 +5,15 @@ For example, string.sub should never use a _pos to substring, only an _offset.
 Wish I had some static typing here. We're not going to try to write tests to catch issues like this.
 
 -- manual tests
-file load:
-  cursor_line = 1
-  first line is a drawing -> cursor_line = 2
-click on text -> cursor moves
-click on first character of text -> cursor on first character of text
-click to right of text -> cursor past end of line
-click to right of wrapped text -> cursor on final character of line
-click on drawing -> cursor doesn't move
-cursor past end of line -> renders
-create drawing -> cursor bumps down below drawing
-backspace
-  cursor_pos == 0, previous line is a drawing -> delete drawing, cursor still visible at start of line
-  cursor_pos == 0, previous line is text -> join lines, cursor still at same character
-
 drawing
   draw a line, circle, rectangle, square, polygon
   select a point and move it
   select a point and name it
 
-enter
-  cursor_pos == 0 -> insert empty line above current line
-
-scrolling:
-  given moby dick, a file containing all text:
-  page up moves top line on screen to bottom
-  page down moves bottom line on screen to top
-  cursor remains on screen
-  cursor remains on text line
-  'up' arrow with cursor at top of screen scrolls up one line (drawings still fully in or out)
-    if cursor line wrapped before, it scrolls up by only one screen line
-    if previous line (above top of screen) wrapped, it scrolls up by only one screen line
-  'down' arrow with cursor at bottom of screen scrolls down one line (drawings still fully in or out)
-    if cursor line wrapped before, it scrolls down by only one screen line
-
 persistence:
   draw a line, circle, rectangle, square, polygon, quit, restart. All the shapes you drew should still be visible.
   select a point and name it, quit, restart. Name is still visible.
 
-clipboard:
-  cut/copy without making a selection
-
 resize:
   create a file containing a long line of characters without spaces. try
   resizing the window vertically and horizontally, as far as possible.

text_tests.lua

@@ -1,6 +1,42 @@
 -- major tests for text editing flows
 -- This still isn't quite as thorough as I'd like.
 
+function test_initial_state()
+  io.write('\ntest_initial_state')
+  App.screen.init{width=120, height=60}
+  Lines = load_array{}
+  App.draw()
+  check_eq(#Lines, 1, 'F - test_initial_state/#lines')
+  check_eq(Cursor1.line, 1, 'F - test_initial_state/cursor:line')
+  check_eq(Cursor1.pos, 1, 'F - test_initial_state/cursor:pos')
+  check_eq(Screen_top1.line, 1, 'F - test_initial_state/screen_top:line')
+  check_eq(Screen_top1.pos, 1, 'F - test_initial_state/screen_top:pos')
+end
+
+function test_click_to_create_drawing()
+  io.write('\ntest_click_to_create_drawing')
+  App.screen.init{width=120, height=60}
+  Lines = load_array{}
+  App.draw()
+  App.run_after_mouse_click(8,Margin_top+8, 1)
+  -- cursor skips drawing to always remain on text
+  check_eq(#Lines, 2, 'F - test_click_to_create_drawing/#lines')
+  check_eq(Cursor1.line, 2, 'F - test_click_to_create_drawing/cursor')
+end
+
+function test_backspace_to_delete_drawing()
+  io.write('\ntest_backspace_to_delete_drawing')
+  -- display a drawing followed by a line of text (you shouldn't ever have a drawing right at the end)
+  App.screen.init{width=120, height=60}
+  Lines = load_array{'```lines', '```', ''}
+  -- cursor is on text as always (outside tests this will get initialized correctly)
+  Cursor1.line = 2
+  -- backspacing deletes the drawing
+  App.run_after_keychord('backspace')
+  check_eq(#Lines, 1, 'F - test_backspace_to_delete_drawing/#lines')
+  check_eq(Cursor1.line, 1, 'F - test_backspace_to_delete_drawing/cursor')
+end
+
 function test_insert_first_character()
   io.write('\ntest_insert_first_character')
   App.screen.init{width=120, height=60}
@@ -202,6 +238,23 @@ function test_insert_newline()
   App.screen.check(y, 'def', 'F - test_insert_newline/screen:3')
 end
 
+function test_insert_newline_at_start_of_line()
+  io.write('\ntest_insert_newline_at_start_of_line')
+  -- display a line
+  App.screen.init{width=25+30, height=60}
+  Lines = load_array{'abc'}
+  Line_width = App.screen.width
+  Cursor1 = {line=1, pos=1}
+  Screen_top1 = {line=1, pos=1}
+  Screen_bottom1 = {}
+  -- hitting the enter key splits the line
+  App.run_after_keychord('return')
+  check_eq(Cursor1.line, 2, 'F - test_insert_newline_at_start_of_line/cursor:line')
+  check_eq(Cursor1.pos, 1, 'F - test_insert_newline_at_start_of_line/cursor:pos')
+  check_eq(Lines[1].data, '', 'F - test_insert_newline_at_start_of_line/data:1')
+  check_eq(Lines[2].data, 'abc', 'F - test_insert_newline_at_start_of_line/data:2')
+end
+
 function test_insert_from_clipboard()
   io.write('\ntest_insert_from_clipboard')
   -- display a few lines
@@ -1017,6 +1070,18 @@ function test_backspace_can_scroll_up_screen_line()
   check_eq(Cursor1.pos, 4, 'F - test_backspace_can_scroll_up_screen_line/cursor:pos')
 end
 
+function test_backspace_past_line_boundary()
+  io.write('\ntest_backspace_past_line_boundary')
+  -- position cursor at start of a (non-first) line
+  App.screen.init{width=25+30, height=60}
+  Lines = load_array{'abc', 'def'}
+  Line_width = App.screen.width
+  Cursor1 = {line=2, pos=1}
+  -- backspace joins with previous line
+  App.run_after_keychord('backspace')
+  check_eq(Lines[1].data, 'abcdef', "F - test_backspace_past_line_boundary")
+end
+
 -- some tests for operating over selections created using Shift- chords
 -- we're just testing delete_selection, and it works the same for all keys