test: reorg #15698

Problem:
Subdirectories like "visual", "insert", "normal" encourage people to
separate *related* tests for no good reason.  Typically the _mode_ is
not the relevant topic of a test (and when it is, _then_ create
an appropriate describe() or it()).

Solution:
- Delete the various `test/functional/<mode>/` subdirectories, move
  their tests to more meaningful topics.
- Rename `…/normal/` to `…/editor/`.
  - Move or merge `…/visual/*` and `…/insert/*` tests into here where
    appropriate.
- Rename `…/eval/` to `…/vimscript/`.
  - Move `…/viml/*` into here also.

* test(reorg): insert/* => editor/mode_insert_spec.lua
* test(reorg): cmdline/* => editor/mode_cmdline_spec.lua
* test(reorg): eval core tests => eval_spec.lua

1 files changed, 28 insertions, 0 deletions

diff --git a/test/functional/vimscript/operators_spec.lua b/test/functional/vimscript/operators_spec.lua
new file mode 100644
index 0000000000..4d07bc1b05
--- /dev/null
+++ b/test/functional/vimscript/operators_spec.lua
@@ -0,0 +1,28 @@
+local helpers = require('test.functional.helpers')(after_each)
+local eq = helpers.eq
+local eval = helpers.eval
+local clear = helpers.clear
+
+describe('Division operator', function()
+  before_each(clear)
+
+  it('returns infinity on {positive}/0.0', function()
+    eq('str2float(\'inf\')', eval('string(1.0/0.0)'))
+    eq('str2float(\'inf\')', eval('string(1.0e-100/0.0)'))
+    eq('str2float(\'inf\')', eval('string(1.0e+100/0.0)'))
+    eq('str2float(\'inf\')', eval('string((1.0/0.0)/0.0)'))
+  end)
+
+  it('returns -infinity on {negative}/0.0', function()
+    eq('-str2float(\'inf\')', eval('string((-1.0)/0.0)'))
+    eq('-str2float(\'inf\')', eval('string((-1.0e-100)/0.0)'))
+    eq('-str2float(\'inf\')', eval('string((-1.0e+100)/0.0)'))
+    eq('-str2float(\'inf\')', eval('string((-1.0/0.0)/0.0)'))
+  end)
+
+  it('returns NaN on 0.0/0.0', function()
+    eq('str2float(\'nan\')', eval('string(0.0/0.0)'))
+    eq('str2float(\'nan\')', eval('string(-(0.0/0.0))'))
+    eq('str2float(\'nan\')', eval('string((-0.0)/0.0)'))
+  end)
+end)