2156 - split edit.mu into multiple files

Now you can bring up the programming environment by saying:

  $ mu edit

The files under edit aren't yet *layers*, though, they have a few
dependencies that we need to clean up.

1 files changed, 111 insertions, 0 deletions

diff --git a/edit/007-sandbox-delete.mu b/edit/007-sandbox-delete.mu
new file mode 100644
index 00000000..b4b317e0
--- /dev/null
+++ b/edit/007-sandbox-delete.mu
@@ -0,0 +1,111 @@
+## deleting sandboxes
+
+scenario deleting-sandboxes [
+  $close-trace  # trace too long
+  assume-screen 100/width, 15/height
+  1:address:array:character <- new []
+  2:address:array:character <- new []
+  3:address:programming-environment-data <- new-programming-environment screen:address, 1:address:array:character, 2:address:array:character
+  # run a few commands
+  assume-console [
+    left-click 1, 80
+    type [divide-with-remainder 11, 3]
+    press F4
+    type [add 2, 2]
+    press F4
+  ]
+  run [
+    event-loop screen:address, console:address, 3:address:programming-environment-data
+  ]
+  screen-should-contain [
+    .                                                                                 run (F4)           .
+    .                                                  ┊                                                 .
+    .┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┊━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━.
+    .                                                  ┊                                                x.
+    .                                                  ┊add 2, 2                                         .
+    .                                                  ┊4                                                .
+    .                                                  ┊━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━.
+    .                                                  ┊                                                x.
+    .                                                  ┊divide-with-remainder 11, 3                      .
+    .                                                  ┊3                                                .
+    .                                                  ┊2                                                .
+    .                                                  ┊━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━.
+    .                                                  ┊                                                 .
+  ]
+  # delete second sandbox
+  assume-console [
+    left-click 7, 99
+  ]
+  run [
+    event-loop screen:address, console:address, 3:address:programming-environment-data
+  ]
+  screen-should-contain [
+    .                                                                                 run (F4)           .
+    .                                                  ┊                                                 .
+    .┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┊━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━.
+    .                                                  ┊                                                x.
+    .                                                  ┊add 2, 2                                         .
+    .                                                  ┊4                                                .
+    .                                                  ┊━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━.
+    .                                                  ┊                                                 .
+    .                                                  ┊                                                 .
+  ]
+  # delete first sandbox
+  assume-console [
+    left-click 3, 99
+  ]
+  run [
+    event-loop screen:address, console:address, 3:address:programming-environment-data
+  ]
+  screen-should-contain [
+    .                                                                                 run (F4)           .
+    .                                                  ┊                                                 .
+    .┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┊━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━.
+    .                                                  ┊                                                 .
+    .                                                  ┊                                                 .
+  ]
+]
+
+after <global-touch> [
+  # on a sandbox delete icon? process delete
+  {
+    was-delete?:boolean <- delete-sandbox *t, env
+    break-unless was-delete?
+    hide-screen screen
+    screen <- render-sandbox-side screen, env
+    screen <- update-cursor screen, recipes, current-sandbox, *sandbox-in-focus?
+    show-screen screen
+    loop +next-event:label
+  }
+]
+
+# was-deleted?:boolean <- delete-sandbox t:touch-event, env:address:programming-environment-data
+recipe delete-sandbox [
+  local-scope
+  t:touch-event <- next-ingredient
+  env:address:programming-environment-data <- next-ingredient
+  click-column:number <- get t, column:offset
+  current-sandbox:address:editor-data <- get *env, current-sandbox:offset
+  right:number <- get *current-sandbox, right:offset
+  at-right?:boolean <- equal click-column, right
+  reply-unless at-right?, 0/false
+  click-row:number <- get t, row:offset
+  prev:address:address:sandbox-data <- get-address *env, sandbox:offset
+  curr:address:sandbox-data <- get *env, sandbox:offset
+  {
+    break-unless curr
+    # more sandboxes to check
+    {
+      target-row:number <- get *curr, starting-row-on-screen:offset
+      delete-curr?:boolean <- equal target-row, click-row
+      break-unless delete-curr?
+      # delete this sandbox, rerender and stop
+      *prev <- get *curr, next-sandbox:offset
+      reply 1/true
+    }
+    prev <- get-address *curr, next-sandbox:offset
+    curr <- get *curr, next-sandbox:offset
+    loop
+  }
+  reply 0/false
+]