howl.ui.ActionBuffer

buf = ActionBuffer!

before_each -> buf.text = ''

behaves like a Buffer

buf.text = 'hello'
assert.equal buf.text, 'hello'
buf\append ' world'
assert.equal buf.text, 'hello world'

does not collection undo revisions by default

assert.is_false ActionBuffer().collect_revisions

is never modified

buf\append 'hello'
buf\insert 'hi', 1
assert.is_false buf.modified
buf.modified = true
assert.is_false buf.modified

modify(f)

runs f with the buffer writable, restoring read_only afterwards

for read_only in *{true, false}
  b = ActionBuffer!
  b.read_only = read_only
  b\modify -> b\append 'hello'
  assert.equal 'hello', b.text
  assert.equal read_only, b.read_only

.insert(object, pos[ , style])

(with no specified style)

inserts the object with no specific style and returns the next position

assert.equal 6, buf\insert 'hello', 1
assert.equal 'hello', buf.text
assert.is_nil style.at_pos(buf, 1)

returns <pos> and leaves the buffer untouched for an empty string

assert.equal 1, buf\insert('', 1)
assert.equal '', buf.text

(with style specified)

styles the object with the specified style

buf.text = '˫˫'
assert.equal 7, buf\insert('hƏllo', 2, 'keyword')
assert.is_nil (style.at_pos(buf, 1))
assert.equal 'keyword', (style.at_pos(buf, 2))
assert.equal 'keyword', (style.at_pos(buf, 6))
assert.is_nil (style.at_pos(buf, 7))

returns <pos> and leaves the buffer untouched for an empty string

assert.equal 1, buf\insert('', 1, 'keyword')
assert.equal '', buf.text

(when object is a styled object (.styles is present))

inserts the corresponding .text and returns the next position

assert.equal 4, buf\insert('foo', 1)
chunk = buf\chunk(1, 3)
assert.equal 7, buf\insert chunk, 4
assert.equal 'foofoo', buf.text

styles the inserted .text using .styles for the styling

buf\insert {text: 'styled', styles: { 2, 'keyword', 3, 3, 'number', 6 }}, 1
assert.is_nil (style.at_pos(buf, 1))
assert.equal 'keyword', (style.at_pos(buf, 2))
assert.equal 'number', (style.at_pos(buf, 3))
assert.equal 'number', (style.at_pos(buf, 5))
assert.is_nil (style.at_pos(buf, 6))
assert.equal 'styled', buf.text

still returns the next position

assert.equal 3, buf\insert StyledText('åö', {}), 1

ignores any given <style> parameter

buf\insert StyledText('foo', { 1, 'number', 4 }), 1, 'keyword'
assert.equal 'number', (style.at_pos(buf, 1))

.append(text, style)

(with no specified style)

appends the text with no specific style and returns the next position

buf.text = 'hello'
assert.equal #'hello world' + 1, buf\append ' world'
assert.is_nil (style.at_pos(buf, 7))

(with style specified)

styles the text with the specified style

buf.text = '˫'
buf\append 'hƏllo', 'keyword'
assert.is_nil (style.at_pos(buf, 1))
assert.equal 'keyword', (style.at_pos(buf, 2))
assert.equal 'keyword', (style.at_pos(buf, 6))

(when object is a styled object)

appends the corresponding text and returns the next position

buf\insert 'foo', 1
chunk = buf\chunk(1, 3)
assert.equals 7, buf\append chunk
assert.equal 'foofoo', buf.text

styles the inserted text using .styles for the styling

buf.text = 'foo'
object = StyledText('bar', {1, 'number', 2, 2, 'keyword', 3})
buf\insert object, 4
assert.equal 'foobar', buf.text
assert.equal 'number', (style.at_pos(buf, 4))
assert.equal 'keyword', (style.at_pos(buf, 5))
assert.is_nil (style.at_pos(buf, 6))

still returns the next position

assert.equal 3, buf\append StyledText('åö', {})

ignores any given <style> parameter

buf\append StyledText('foo', { 1, 'number', 4 }), 'keyword'
assert.equal 'number', (style.at_pos(buf, 1))

style(start_pos, end_pos, style)

applies <style> for the inclusive text range given

buf.text = 'hƏlɩo'
buf\style 2, 4, 'keyword'
assert.is_nil (style.at_pos(buf, 1))
assert.equal 'keyword', (style.at_pos(buf, 2))
assert.equal 'keyword', (style.at_pos(buf, 4))
assert.is_nil (style.at_pos(buf, 5))

(resource management)

buffers are collected properly

b = ActionBuffer!
buffers = setmetatable { b }, __mode: 'v'
b = nil
collectgarbage!
assert.is_nil buffers[1]