pulsar/spec/display-buffer-spec.coffee

1014 lines
48 KiB
CoffeeScript

DisplayBuffer = require '../src/display-buffer'
_ = require 'underscore-plus'
describe "DisplayBuffer", ->
[displayBuffer, buffer, changeHandler, tabLength] = []
beforeEach ->
tabLength = 2
buffer = atom.project.bufferForPathSync('sample.js')
displayBuffer = new DisplayBuffer({buffer, tabLength})
changeHandler = jasmine.createSpy 'changeHandler'
displayBuffer.on 'changed', changeHandler
waitsForPromise ->
atom.packages.activatePackage('language-javascript')
afterEach ->
displayBuffer.destroy()
buffer.release()
describe "::copy()", ->
it "creates a new DisplayBuffer with the same initial state", ->
marker1 = displayBuffer.markBufferRange([[1, 2], [3, 4]], id: 1)
marker2 = displayBuffer.markBufferRange([[2, 3], [4, 5]], reversed: true, id: 2)
marker3 = displayBuffer.markBufferPosition([5, 6], id: 3)
displayBuffer.createFold(3, 5)
displayBuffer2 = displayBuffer.copy()
expect(displayBuffer2.id).not.toBe displayBuffer.id
expect(displayBuffer2.buffer).toBe displayBuffer.buffer
expect(displayBuffer2.getTabLength()).toBe displayBuffer.getTabLength()
expect(displayBuffer2.getMarkerCount()).toEqual displayBuffer.getMarkerCount()
expect(displayBuffer2.findMarker(id: 1)).toEqual marker1
expect(displayBuffer2.findMarker(id: 2)).toEqual marker2
expect(displayBuffer2.findMarker(id: 3)).toEqual marker3
expect(displayBuffer2.isFoldedAtBufferRow(3)).toBeTruthy()
# can diverge from origin
displayBuffer2.unfoldBufferRow(3)
expect(displayBuffer2.isFoldedAtBufferRow(3)).not.toBe displayBuffer.isFoldedAtBufferRow(3)
describe "when the buffer changes", ->
it "renders line numbers correctly", ->
originalLineCount = displayBuffer.getLineCount()
oneHundredLines = [0..100].join("\n")
buffer.insert([0,0], oneHundredLines)
expect(displayBuffer.getLineCount()).toBe 100 + originalLineCount
describe "soft wrapping", ->
beforeEach ->
displayBuffer.setSoftWrap(true)
displayBuffer.setEditorWidthInChars(50)
changeHandler.reset()
describe "rendering of soft-wrapped lines", ->
describe "when editor.softWrapAtPreferredLineLength is set", ->
it "uses the preferred line length as the soft wrap column when it is less than the configured soft wrap column", ->
atom.config.set('editor.preferredLineLength', 100)
atom.config.set('editor.softWrapAtPreferredLineLength', true)
expect(displayBuffer.lineForRow(10).text).toBe ' return '
atom.config.set('editor.preferredLineLength', 5)
expect(displayBuffer.lineForRow(10).text).toBe 'funct'
atom.config.set('editor.softWrapAtPreferredLineLength', false)
expect(displayBuffer.lineForRow(10).text).toBe ' return '
describe "when the line is shorter than the max line length", ->
it "renders the line unchanged", ->
expect(displayBuffer.lineForRow(0).text).toBe buffer.lineForRow(0)
describe "when the line is empty", ->
it "renders the empty line", ->
expect(displayBuffer.lineForRow(13).text).toBe ''
describe "when there is a non-whitespace character at the max length boundary", ->
describe "when there is whitespace before the boundary", ->
it "wraps the line at the end of the first whitespace preceding the boundary", ->
expect(displayBuffer.lineForRow(10).text).toBe ' return '
expect(displayBuffer.lineForRow(11).text).toBe 'sort(left).concat(pivot).concat(sort(right));'
describe "when there is no whitespace before the boundary", ->
it "wraps the line exactly at the boundary since there's no more graceful place to wrap it", ->
buffer.setTextInRange([[0, 0], [1, 0]], 'abcdefghijklmnopqrstuvwxyz\n')
displayBuffer.setEditorWidthInChars(10)
expect(displayBuffer.lineForRow(0).text).toBe 'abcdefghij'
expect(displayBuffer.lineForRow(1).text).toBe 'klmnopqrst'
expect(displayBuffer.lineForRow(2).text).toBe 'uvwxyz'
describe "when there is a whitespace character at the max length boundary", ->
it "wraps the line at the first non-whitespace character following the boundary", ->
expect(displayBuffer.lineForRow(3).text).toBe ' var pivot = items.shift(), current, left = [], '
expect(displayBuffer.lineForRow(4).text).toBe 'right = [];'
describe "when there are hard tabs", ->
beforeEach ->
buffer.setText(buffer.getText().replace(new RegExp(' ', 'g'), '\t'))
it "correctly tokenizes the hard tabs", ->
expect(displayBuffer.lineForRow(3).tokens[0].isHardTab).toBeTruthy()
expect(displayBuffer.lineForRow(3).tokens[1].isHardTab).toBeTruthy()
describe "when the buffer changes", ->
describe "when buffer lines are updated", ->
describe "when whitespace is added after the max line length", ->
it "adds whitespace to the end of the current line and wraps an empty line", ->
fiftyCharacters = _.multiplyString("x", 50)
buffer.setText(fiftyCharacters)
buffer.insert([0, 51], " ")
describe "when the update makes a soft-wrapped line shorter than the max line length", ->
it "rewraps the line and emits a change event", ->
buffer.delete([[6, 24], [6, 42]])
expect(displayBuffer.lineForRow(7).text).toBe ' current < pivot ? : right.push(current);'
expect(displayBuffer.lineForRow(8).text).toBe ' }'
expect(changeHandler).toHaveBeenCalled()
[[event]]= changeHandler.argsForCall
expect(event).toEqual(start: 7, end: 8, screenDelta: -1, bufferDelta: 0)
describe "when the update causes a line to softwrap an additional time", ->
it "rewraps the line and emits a change event", ->
buffer.insert([6, 28], '1234567890')
expect(displayBuffer.lineForRow(7).text).toBe ' current < pivot ? '
expect(displayBuffer.lineForRow(8).text).toBe 'left1234567890.push(current) : '
expect(displayBuffer.lineForRow(9).text).toBe 'right.push(current);'
expect(displayBuffer.lineForRow(10).text).toBe ' }'
expect(changeHandler).toHaveBeenCalledWith(start: 7, end: 8, screenDelta: 1, bufferDelta: 0)
describe "when buffer lines are inserted", ->
it "inserts / updates wrapped lines and emits a change event", ->
buffer.insert([6, 21], '1234567890 abcdefghij 1234567890\nabcdefghij')
expect(displayBuffer.lineForRow(7).text).toBe ' current < pivot1234567890 abcdefghij '
expect(displayBuffer.lineForRow(8).text).toBe '1234567890'
expect(displayBuffer.lineForRow(9).text).toBe 'abcdefghij ? left.push(current) : '
expect(displayBuffer.lineForRow(10).text).toBe 'right.push(current);'
expect(changeHandler).toHaveBeenCalledWith(start: 7, end: 8, screenDelta: 2, bufferDelta: 1)
describe "when buffer lines are removed", ->
it "removes lines and emits a change event", ->
buffer.setTextInRange([[3, 21], [7, 5]], ';')
expect(displayBuffer.lineForRow(3).text).toBe ' var pivot = items;'
expect(displayBuffer.lineForRow(4).text).toBe ' return '
expect(displayBuffer.lineForRow(5).text).toBe 'sort(left).concat(pivot).concat(sort(right));'
expect(displayBuffer.lineForRow(6).text).toBe ' };'
expect(changeHandler).toHaveBeenCalledWith(start: 3, end: 9, screenDelta: -6, bufferDelta: -4)
describe "when a newline is inserted, deleted, and re-inserted at the end of a wrapped line (regression)", ->
it "correctly renders the original wrapped line", ->
buffer = atom.project.buildBufferSync(null, '')
displayBuffer = new DisplayBuffer({buffer, tabLength, editorWidthInChars: 30, softWrap: true})
buffer.insert([0, 0], "the quick brown fox jumps over the lazy dog.")
buffer.insert([0, Infinity], '\n')
buffer.delete([[0, Infinity], [1, 0]])
buffer.insert([0, Infinity], '\n')
expect(displayBuffer.lineForRow(0).text).toBe "the quick brown fox jumps over "
expect(displayBuffer.lineForRow(1).text).toBe "the lazy dog."
expect(displayBuffer.lineForRow(2).text).toBe ""
describe "position translation", ->
it "translates positions accounting for wrapped lines", ->
# before any wrapped lines
expect(displayBuffer.screenPositionForBufferPosition([0, 5])).toEqual([0, 5])
expect(displayBuffer.bufferPositionForScreenPosition([0, 5])).toEqual([0, 5])
expect(displayBuffer.screenPositionForBufferPosition([0, 29])).toEqual([0, 29])
expect(displayBuffer.bufferPositionForScreenPosition([0, 29])).toEqual([0, 29])
# on a wrapped line
expect(displayBuffer.screenPositionForBufferPosition([3, 5])).toEqual([3, 5])
expect(displayBuffer.bufferPositionForScreenPosition([3, 5])).toEqual([3, 5])
expect(displayBuffer.screenPositionForBufferPosition([3, 50])).toEqual([3, 50])
expect(displayBuffer.screenPositionForBufferPosition([3, 51])).toEqual([3, 50])
expect(displayBuffer.bufferPositionForScreenPosition([4, 0])).toEqual([3, 51])
expect(displayBuffer.bufferPositionForScreenPosition([3, 50])).toEqual([3, 50])
expect(displayBuffer.screenPositionForBufferPosition([3, 62])).toEqual([4, 11])
expect(displayBuffer.bufferPositionForScreenPosition([4, 11])).toEqual([3, 62])
# following a wrapped line
expect(displayBuffer.screenPositionForBufferPosition([4, 5])).toEqual([5, 5])
expect(displayBuffer.bufferPositionForScreenPosition([5, 5])).toEqual([4, 5])
# clip screen position inputs before translating
expect(displayBuffer.bufferPositionForScreenPosition([-5, -5])).toEqual([0, 0])
expect(displayBuffer.bufferPositionForScreenPosition([Infinity, Infinity])).toEqual([12, 2])
expect(displayBuffer.bufferPositionForScreenPosition([3, -5])).toEqual([3, 0])
expect(displayBuffer.bufferPositionForScreenPosition([3, Infinity])).toEqual([3, 50])
describe ".setEditorWidthInChars(length)", ->
it "changes the length at which lines are wrapped and emits a change event for all screen lines", ->
displayBuffer.setEditorWidthInChars(40)
expect(tokensText displayBuffer.lineForRow(4).tokens).toBe 'left = [], right = [];'
expect(tokensText displayBuffer.lineForRow(5).tokens).toBe ' while(items.length > 0) {'
expect(tokensText displayBuffer.lineForRow(12).tokens).toBe 'sort(left).concat(pivot).concat(sort(rig'
expect(changeHandler).toHaveBeenCalledWith(start: 0, end: 15, screenDelta: 3, bufferDelta: 0)
it "only allows positive widths to be assigned", ->
displayBuffer.setEditorWidthInChars(0)
expect(displayBuffer.editorWidthInChars).not.toBe 0
displayBuffer.setEditorWidthInChars(-1)
expect(displayBuffer.editorWidthInChars).not.toBe -1
describe "primitive folding", ->
beforeEach ->
displayBuffer.destroy()
buffer.release()
buffer = atom.project.bufferForPathSync('two-hundred.txt')
displayBuffer = new DisplayBuffer({buffer, tabLength})
displayBuffer.on 'changed', changeHandler
describe "when folds are created and destroyed", ->
describe "when a fold spans multiple lines", ->
it "replaces the lines spanned by the fold with a placeholder that references the fold object", ->
fold = displayBuffer.createFold(4, 7)
expect(fold).toBeDefined()
[line4, line5] = displayBuffer.linesForRows(4, 5)
expect(line4.fold).toBe fold
expect(line4.text).toMatch /^4-+/
expect(line5.text).toBe '8'
expect(changeHandler).toHaveBeenCalledWith(start: 4, end: 7, screenDelta: -3, bufferDelta: 0)
changeHandler.reset()
fold.destroy()
[line4, line5] = displayBuffer.linesForRows(4, 5)
expect(line4.fold).toBeUndefined()
expect(line4.text).toMatch /^4-+/
expect(line5.text).toBe '5'
expect(changeHandler).toHaveBeenCalledWith(start: 4, end: 4, screenDelta: 3, bufferDelta: 0)
describe "when a fold spans a single line", ->
it "renders a fold placeholder for the folded line but does not skip any lines", ->
fold = displayBuffer.createFold(4, 4)
[line4, line5] = displayBuffer.linesForRows(4, 5)
expect(line4.fold).toBe fold
expect(line4.text).toMatch /^4-+/
expect(line5.text).toBe '5'
expect(changeHandler).toHaveBeenCalledWith(start: 4, end: 4, screenDelta: 0, bufferDelta: 0)
# Line numbers don't actually change, but it's not worth the complexity to have this
# be false for single line folds since they are so rare
changeHandler.reset()
fold.destroy()
[line4, line5] = displayBuffer.linesForRows(4, 5)
expect(line4.fold).toBeUndefined()
expect(line4.text).toMatch /^4-+/
expect(line5.text).toBe '5'
expect(changeHandler).toHaveBeenCalledWith(start: 4, end: 4, screenDelta: 0, bufferDelta: 0)
describe "when a fold is nested within another fold", ->
it "does not render the placeholder for the inner fold until the outer fold is destroyed", ->
innerFold = displayBuffer.createFold(6, 7)
outerFold = displayBuffer.createFold(4, 8)
[line4, line5] = displayBuffer.linesForRows(4, 5)
expect(line4.fold).toBe outerFold
expect(line4.text).toMatch /4-+/
expect(line5.text).toMatch /9-+/
outerFold.destroy()
[line4, line5, line6, line7] = displayBuffer.linesForRows(4, 7)
expect(line4.fold).toBeUndefined()
expect(line4.text).toMatch /^4-+/
expect(line5.text).toBe '5'
expect(line6.fold).toBe innerFold
expect(line6.text).toBe '6'
expect(line7.text).toBe '8'
it "allows the outer fold to start at the same location as the inner fold", ->
innerFold = displayBuffer.createFold(4, 6)
outerFold = displayBuffer.createFold(4, 8)
[line4, line5] = displayBuffer.linesForRows(4, 5)
expect(line4.fold).toBe outerFold
expect(line4.text).toMatch /4-+/
expect(line5.text).toMatch /9-+/
describe "when creating a fold where one already exists", ->
it "returns existing fold and does't create new fold", ->
fold = displayBuffer.createFold(0,10)
expect(displayBuffer.findMarkers(class: 'fold').length).toBe 1
newFold = displayBuffer.createFold(0,10)
expect(newFold).toBe fold
expect(displayBuffer.findMarkers(class: 'fold').length).toBe 1
describe "when a fold is created inside an existing folded region", ->
it "creates/destroys the fold, but does not trigger change event", ->
outerFold = displayBuffer.createFold(0, 10)
changeHandler.reset()
innerFold = displayBuffer.createFold(2, 5)
expect(changeHandler).not.toHaveBeenCalled()
[line0, line1] = displayBuffer.linesForRows(0, 1)
expect(line0.fold).toBe outerFold
expect(line1.fold).toBeUndefined()
changeHandler.reset()
innerFold.destroy()
expect(changeHandler).not.toHaveBeenCalled()
[line0, line1] = displayBuffer.linesForRows(0, 1)
expect(line0.fold).toBe outerFold
expect(line1.fold).toBeUndefined()
describe "when there is another display buffer pointing to the same buffer", ->
it "does not create folds in the other display buffer", ->
otherDisplayBuffer = new DisplayBuffer({buffer, tabLength})
displayBuffer.createFold(2, 4)
expect(otherDisplayBuffer.foldsStartingAtBufferRow(2).length).toBe 0
describe "when the buffer changes", ->
[fold1, fold2] = []
beforeEach ->
fold1 = displayBuffer.createFold(2, 4)
fold2 = displayBuffer.createFold(6, 8)
changeHandler.reset()
describe "when the old range surrounds a fold", ->
beforeEach ->
buffer.setTextInRange([[1, 0], [5, 1]], 'party!')
it "removes the fold and replaces the selection with the new text", ->
expect(displayBuffer.lineForRow(0).text).toBe "0"
expect(displayBuffer.lineForRow(1).text).toBe "party!"
expect(displayBuffer.lineForRow(2).fold).toBe fold2
expect(displayBuffer.lineForRow(3).text).toMatch /^9-+/
expect(changeHandler).toHaveBeenCalledWith(start: 1, end: 3, screenDelta: -2, bufferDelta: -4)
describe "when the changes is subsequently undone", ->
xit "restores destroyed folds", ->
buffer.undo()
expect(displayBuffer.lineForRow(2).text).toBe '2'
expect(displayBuffer.lineForRow(2).fold).toBe fold1
expect(displayBuffer.lineForRow(3).text).toBe '5'
describe "when the old range surrounds two nested folds", ->
it "removes both folds and replaces the selection with the new text", ->
displayBuffer.createFold(2, 9)
changeHandler.reset()
buffer.setTextInRange([[1, 0], [10, 0]], 'goodbye')
expect(displayBuffer.lineForRow(0).text).toBe "0"
expect(displayBuffer.lineForRow(1).text).toBe "goodbye10"
expect(displayBuffer.lineForRow(2).text).toBe "11"
expect(changeHandler).toHaveBeenCalledWith(start: 1, end: 3, screenDelta: -2, bufferDelta: -9)
describe "when multiple changes happen above the fold", ->
it "repositions folds correctly", ->
buffer.delete([[1, 1], [2, 0]])
buffer.insert([0, 1], "\nnew")
expect(fold1.getStartRow()).toBe 2
expect(fold1.getEndRow()).toBe 4
describe "when the old range precedes lines with a fold", ->
describe "when the new range precedes lines with a fold", ->
it "updates the buffer and re-positions subsequent folds", ->
buffer.setTextInRange([[0, 0], [1, 1]], 'abc')
expect(displayBuffer.lineForRow(0).text).toBe "abc"
expect(displayBuffer.lineForRow(1).fold).toBe fold1
expect(displayBuffer.lineForRow(2).text).toBe "5"
expect(displayBuffer.lineForRow(3).fold).toBe fold2
expect(displayBuffer.lineForRow(4).text).toMatch /^9-+/
expect(changeHandler).toHaveBeenCalledWith(start: 0, end: 1, screenDelta: -1, bufferDelta: -1)
changeHandler.reset()
fold1.destroy()
expect(displayBuffer.lineForRow(0).text).toBe "abc"
expect(displayBuffer.lineForRow(1).text).toBe "2"
expect(displayBuffer.lineForRow(3).text).toMatch /^4-+/
expect(displayBuffer.lineForRow(4).text).toBe "5"
expect(displayBuffer.lineForRow(5).fold).toBe fold2
expect(displayBuffer.lineForRow(6).text).toMatch /^9-+/
expect(changeHandler).toHaveBeenCalledWith(start: 1, end: 1, screenDelta: 2, bufferDelta: 0)
describe "when the old range straddles the beginning of a fold", ->
it "destroys the fold", ->
buffer.setTextInRange([[1, 1], [3, 0]], "a\nb\nc\nd\n")
expect(displayBuffer.lineForRow(1).text).toBe '1a'
expect(displayBuffer.lineForRow(2).text).toBe 'b'
expect(displayBuffer.lineForRow(2).fold).toBeUndefined()
expect(displayBuffer.lineForRow(3).text).toBe 'c'
describe "when the old range follows a fold", ->
it "re-positions the screen ranges for the change event based on the preceding fold", ->
buffer.setTextInRange([[10, 0], [11, 0]], 'abc')
expect(displayBuffer.lineForRow(1).text).toBe "1"
expect(displayBuffer.lineForRow(2).fold).toBe fold1
expect(displayBuffer.lineForRow(3).text).toBe "5"
expect(displayBuffer.lineForRow(4).fold).toBe fold2
expect(displayBuffer.lineForRow(5).text).toMatch /^9-+/
expect(changeHandler).toHaveBeenCalledWith(start: 6, end: 7, screenDelta: -1, bufferDelta: -1)
describe "when the old range is inside a fold", ->
describe "when the end of the new range precedes the end of the fold", ->
it "updates the fold and ensures the change is present when the fold is destroyed", ->
buffer.insert([3, 0], '\n')
expect(fold1.getStartRow()).toBe 2
expect(fold1.getEndRow()).toBe 5
expect(displayBuffer.lineForRow(1).text).toBe "1"
expect(displayBuffer.lineForRow(2).text).toBe "2"
expect(displayBuffer.lineForRow(2).fold).toBe fold1
expect(displayBuffer.lineForRow(3).text).toMatch "5"
expect(displayBuffer.lineForRow(4).fold).toBe fold2
expect(displayBuffer.lineForRow(5).text).toMatch /^9-+/
expect(changeHandler).toHaveBeenCalledWith(start: 2, end: 2, screenDelta: 0, bufferDelta: 1)
describe "when the end of the new range exceeds the end of the fold", ->
it "expands the fold to contain all the inserted lines", ->
buffer.setTextInRange([[3, 0], [4, 0]], 'a\nb\nc\nd\n')
expect(fold1.getStartRow()).toBe 2
expect(fold1.getEndRow()).toBe 7
expect(displayBuffer.lineForRow(1).text).toBe "1"
expect(displayBuffer.lineForRow(2).text).toBe "2"
expect(displayBuffer.lineForRow(2).fold).toBe fold1
expect(displayBuffer.lineForRow(3).text).toMatch "5"
expect(displayBuffer.lineForRow(4).fold).toBe fold2
expect(displayBuffer.lineForRow(5).text).toMatch /^9-+/
expect(changeHandler).toHaveBeenCalledWith(start: 2, end: 2, screenDelta: 0, bufferDelta: 3)
describe "when the old range straddles the end of the fold", ->
describe "when the end of the new range precedes the end of the fold", ->
it "destroys the fold", ->
fold2.destroy()
buffer.setTextInRange([[3, 0], [6, 0]], 'a\n')
expect(displayBuffer.lineForRow(2).text).toBe '2'
expect(displayBuffer.lineForRow(2).fold).toBeUndefined()
expect(displayBuffer.lineForRow(3).text).toBe 'a'
expect(displayBuffer.lineForRow(4).text).toBe '6'
describe "when the old range is contained to a single line in-between two folds", ->
it "re-renders the line with the placeholder and re-positions the second fold", ->
buffer.insert([5, 0], 'abc\n')
expect(displayBuffer.lineForRow(1).text).toBe "1"
expect(displayBuffer.lineForRow(2).fold).toBe fold1
expect(displayBuffer.lineForRow(3).text).toMatch "abc"
expect(displayBuffer.lineForRow(4).text).toBe "5"
expect(displayBuffer.lineForRow(5).fold).toBe fold2
expect(displayBuffer.lineForRow(6).text).toMatch /^9-+/
expect(changeHandler).toHaveBeenCalledWith(start: 3, end: 3, screenDelta: 1, bufferDelta: 1)
describe "when the change starts at the beginning of a fold but does not extend to the end (regression)", ->
it "preserves a proper mapping between buffer and screen coordinates", ->
expect(displayBuffer.screenPositionForBufferPosition([8, 0])).toEqual [4, 0]
buffer.setTextInRange([[2, 0], [3, 0]], "\n")
expect(displayBuffer.screenPositionForBufferPosition([8, 0])).toEqual [4, 0]
describe "position translation", ->
it "translates positions to account for folded lines and characters and the placeholder", ->
fold = displayBuffer.createFold(4, 7)
# preceding fold: identity
expect(displayBuffer.screenPositionForBufferPosition([3, 0])).toEqual [3, 0]
expect(displayBuffer.screenPositionForBufferPosition([4, 0])).toEqual [4, 0]
expect(displayBuffer.bufferPositionForScreenPosition([3, 0])).toEqual [3, 0]
expect(displayBuffer.bufferPositionForScreenPosition([4, 0])).toEqual [4, 0]
# inside of fold: translate to the start of the fold
expect(displayBuffer.screenPositionForBufferPosition([4, 35])).toEqual [4, 0]
expect(displayBuffer.screenPositionForBufferPosition([5, 5])).toEqual [4, 0]
# following fold
expect(displayBuffer.screenPositionForBufferPosition([8, 0])).toEqual [5, 0]
expect(displayBuffer.screenPositionForBufferPosition([11, 2])).toEqual [8, 2]
expect(displayBuffer.bufferPositionForScreenPosition([5, 0])).toEqual [8, 0]
expect(displayBuffer.bufferPositionForScreenPosition([9, 2])).toEqual [12, 2]
# clip screen positions before translating
expect(displayBuffer.bufferPositionForScreenPosition([-5, -5])).toEqual([0, 0])
expect(displayBuffer.bufferPositionForScreenPosition([Infinity, Infinity])).toEqual([200, 0])
# after fold is destroyed
fold.destroy()
expect(displayBuffer.screenPositionForBufferPosition([8, 0])).toEqual [8, 0]
expect(displayBuffer.screenPositionForBufferPosition([11, 2])).toEqual [11, 2]
expect(displayBuffer.bufferPositionForScreenPosition([5, 0])).toEqual [5, 0]
expect(displayBuffer.bufferPositionForScreenPosition([9, 2])).toEqual [9, 2]
describe ".unfoldBufferRow(row)", ->
it "destroys all folds containing the given row", ->
displayBuffer.createFold(2, 4)
displayBuffer.createFold(2, 6)
displayBuffer.createFold(7, 8)
displayBuffer.createFold(1, 9)
displayBuffer.createFold(11, 12)
expect(displayBuffer.lineForRow(1).text).toBe '1'
expect(displayBuffer.lineForRow(2).text).toBe '10'
displayBuffer.unfoldBufferRow(2)
expect(displayBuffer.lineForRow(1).text).toBe '1'
expect(displayBuffer.lineForRow(2).text).toBe '2'
expect(displayBuffer.lineForRow(7).fold).toBeDefined()
expect(displayBuffer.lineForRow(8).text).toMatch /^9-+/
expect(displayBuffer.lineForRow(10).fold).toBeDefined()
describe ".outermostFoldsInBufferRowRange(startRow, endRow)", ->
it "returns the outermost folds entirely contained in the given row range, exclusive of end row", ->
fold1 = displayBuffer.createFold(4, 7)
fold2 = displayBuffer.createFold(5, 6)
fold3 = displayBuffer.createFold(11, 15)
fold4 = displayBuffer.createFold(12, 13)
fold5 = displayBuffer.createFold(16, 17)
expect(displayBuffer.outermostFoldsInBufferRowRange(3, 18)).toEqual [fold1, fold3, fold5]
expect(displayBuffer.outermostFoldsInBufferRowRange(5, 16)).toEqual [fold3]
describe "::clipScreenPosition(screenPosition, wrapBeyondNewlines: false, wrapAtSoftNewlines: false, skipAtomicTokens: false)", ->
beforeEach ->
displayBuffer.setSoftWrap(true)
displayBuffer.setEditorWidthInChars(50)
it "allows valid positions", ->
expect(displayBuffer.clipScreenPosition([4, 5])).toEqual [4, 5]
expect(displayBuffer.clipScreenPosition([4, 11])).toEqual [4, 11]
it "disallows negative positions", ->
expect(displayBuffer.clipScreenPosition([-1, -1])).toEqual [0, 0]
expect(displayBuffer.clipScreenPosition([-1, 10])).toEqual [0, 0]
expect(displayBuffer.clipScreenPosition([0, -1])).toEqual [0, 0]
it "disallows positions beyond the last row", ->
expect(displayBuffer.clipScreenPosition([1000, 0])).toEqual [15, 2]
expect(displayBuffer.clipScreenPosition([1000, 1000])).toEqual [15, 2]
describe "when wrapBeyondNewlines is false (the default)", ->
it "wraps positions beyond the end of hard newlines to the end of the line", ->
expect(displayBuffer.clipScreenPosition([1, 10000])).toEqual [1, 30]
expect(displayBuffer.clipScreenPosition([4, 30])).toEqual [4, 11]
expect(displayBuffer.clipScreenPosition([4, 1000])).toEqual [4, 11]
describe "when wrapBeyondNewlines is true", ->
it "wraps positions past the end of hard newlines to the next line", ->
expect(displayBuffer.clipScreenPosition([0, 29], wrapBeyondNewlines: true)).toEqual [0, 29]
expect(displayBuffer.clipScreenPosition([0, 30], wrapBeyondNewlines: true)).toEqual [1, 0]
expect(displayBuffer.clipScreenPosition([0, 1000], wrapBeyondNewlines: true)).toEqual [1, 0]
it "wraps positions in the middle of fold lines to the next screen line", ->
displayBuffer.createFold(3, 5)
expect(displayBuffer.clipScreenPosition([3, 5], wrapBeyondNewlines: true)).toEqual [4, 0]
describe "when wrapAtSoftNewlines is false (the default)", ->
it "clips positions at the end of soft-wrapped lines to the character preceding the end of the line", ->
expect(displayBuffer.clipScreenPosition([3, 50])).toEqual [3, 50]
expect(displayBuffer.clipScreenPosition([3, 51])).toEqual [3, 50]
expect(displayBuffer.clipScreenPosition([3, 58])).toEqual [3, 50]
expect(displayBuffer.clipScreenPosition([3, 1000])).toEqual [3, 50]
describe "when wrapAtSoftNewlines is true", ->
it "wraps positions at the end of soft-wrapped lines to the next screen line", ->
expect(displayBuffer.clipScreenPosition([3, 50], wrapAtSoftNewlines: true)).toEqual [3, 50]
expect(displayBuffer.clipScreenPosition([3, 51], wrapAtSoftNewlines: true)).toEqual [4, 0]
expect(displayBuffer.clipScreenPosition([3, 58], wrapAtSoftNewlines: true)).toEqual [4, 0]
expect(displayBuffer.clipScreenPosition([3, 1000], wrapAtSoftNewlines: true)).toEqual [4, 0]
describe "when skipAtomicTokens is false (the default)", ->
it "clips screen positions in the middle of atomic tab characters to the beginning of the character", ->
buffer.insert([0, 0], '\t')
expect(displayBuffer.clipScreenPosition([0, 0])).toEqual [0, 0]
expect(displayBuffer.clipScreenPosition([0, 1])).toEqual [0, 0]
expect(displayBuffer.clipScreenPosition([0, tabLength])).toEqual [0, tabLength]
describe "when skipAtomicTokens is true", ->
it "clips screen positions in the middle of atomic tab characters to the end of the character", ->
buffer.insert([0, 0], '\t')
expect(displayBuffer.clipScreenPosition([0, 0], skipAtomicTokens: true)).toEqual [0, 0]
expect(displayBuffer.clipScreenPosition([0, 1], skipAtomicTokens: true)).toEqual [0, tabLength]
expect(displayBuffer.clipScreenPosition([0, tabLength], skipAtomicTokens: true)).toEqual [0, tabLength]
describe "::screenPositionForBufferPosition(bufferPosition, options)", ->
it "clips the specified buffer position", ->
expect(displayBuffer.screenPositionForBufferPosition([0, 2])).toEqual [0, 2]
expect(displayBuffer.screenPositionForBufferPosition([0, 100000])).toEqual [0, 29]
expect(displayBuffer.screenPositionForBufferPosition([100000, 0])).toEqual [12, 2]
expect(displayBuffer.screenPositionForBufferPosition([100000, 100000])).toEqual [12, 2]
describe "position translation in the presence of hard tabs", ->
it "correctly translates positions on either side of a tab", ->
buffer.setText('\t')
expect(displayBuffer.screenPositionForBufferPosition([0, 1])).toEqual [0, 2]
expect(displayBuffer.bufferPositionForScreenPosition([0, 2])).toEqual [0, 1]
it "correctly translates positions on soft wrapped lines containing tabs", ->
buffer.setText('\t\taa bb cc dd ee ff gg')
displayBuffer.setSoftWrap(true)
displayBuffer.setEditorWidthInChars(10)
expect(displayBuffer.screenPositionForBufferPosition([0, 10], wrapAtSoftNewlines: true)).toEqual [1, 0]
expect(displayBuffer.bufferPositionForScreenPosition([1, 0])).toEqual [0, 10]
describe "::getMaxLineLength()", ->
it "returns the length of the longest screen line", ->
expect(displayBuffer.getMaxLineLength()).toBe 65
buffer.delete([[6, 0], [6, 65]])
expect(displayBuffer.getMaxLineLength()).toBe 62
describe "::destroy()", ->
it "unsubscribes all display buffer markers from their underlying buffer marker (regression)", ->
marker = displayBuffer.markBufferPosition([12, 2])
displayBuffer.destroy()
expect(marker.bufferMarker.getSubscriptionCount()).toBe 0
expect( -> buffer.insert([12, 2], '\n')).not.toThrow()
describe "markers", ->
beforeEach ->
displayBuffer.createFold(4, 7)
describe "marker creation and manipulation", ->
it "allows markers to be created in terms of both screen and buffer coordinates", ->
marker1 = displayBuffer.markScreenRange([[5, 4], [5, 10]])
marker2 = displayBuffer.markBufferRange([[8, 4], [8, 10]])
expect(marker1.getBufferRange()).toEqual [[8, 4], [8, 10]]
expect(marker2.getScreenRange()).toEqual [[5, 4], [5, 10]]
it "emits a 'marker-created' event on the DisplayBuffer whenever a marker is created", ->
displayBuffer.on 'marker-created', markerCreatedHandler = jasmine.createSpy("markerCreatedHandler")
marker1 = displayBuffer.markScreenRange([[5, 4], [5, 10]])
expect(markerCreatedHandler).toHaveBeenCalledWith(marker1)
markerCreatedHandler.reset()
marker2 = buffer.markRange([[5, 4], [5, 10]])
expect(markerCreatedHandler).toHaveBeenCalledWith(displayBuffer.getMarker(marker2.id))
it "allows marker head and tail positions to be manipulated in both screen and buffer coordinates", ->
marker = displayBuffer.markScreenRange([[5, 4], [5, 10]])
marker.setHeadScreenPosition([5, 4])
marker.setTailBufferPosition([5, 4])
expect(marker.isReversed()).toBeFalsy()
expect(marker.getBufferRange()).toEqual [[5, 4], [8, 4]]
marker.setHeadBufferPosition([5, 4])
marker.setTailScreenPosition([5, 4])
expect(marker.isReversed()).toBeTruthy()
expect(marker.getBufferRange()).toEqual [[5, 4], [8, 4]]
it "returns whether a position changed when it is assigned", ->
marker = displayBuffer.markScreenRange([[0, 0], [0, 0]])
expect(marker.setHeadScreenPosition([5, 4])).toBeTruthy()
expect(marker.setHeadScreenPosition([5, 4])).toBeFalsy()
expect(marker.setHeadBufferPosition([1, 0])).toBeTruthy()
expect(marker.setHeadBufferPosition([1, 0])).toBeFalsy()
expect(marker.setTailScreenPosition([5, 4])).toBeTruthy()
expect(marker.setTailScreenPosition([5, 4])).toBeFalsy()
expect(marker.setTailBufferPosition([1, 0])).toBeTruthy()
expect(marker.setTailBufferPosition([1, 0])).toBeFalsy()
describe "marker change events", ->
[markerChangedHandler, marker] = []
beforeEach ->
marker = displayBuffer.markScreenRange([[5, 4], [5, 10]])
marker.on 'changed', markerChangedHandler = jasmine.createSpy("markerChangedHandler")
it "triggers the 'changed' event whenever the markers head's screen position changes in the buffer or on screen", ->
marker.setHeadScreenPosition([8, 20])
expect(markerChangedHandler).toHaveBeenCalled()
expect(markerChangedHandler.argsForCall[0][0]).toEqual {
oldHeadScreenPosition: [5, 10]
oldHeadBufferPosition: [8, 10]
newHeadScreenPosition: [8, 20]
newHeadBufferPosition: [11, 20]
oldTailScreenPosition: [5, 4]
oldTailBufferPosition: [8, 4]
newTailScreenPosition: [5, 4]
newTailBufferPosition: [8, 4]
textChanged: false
isValid: true
}
markerChangedHandler.reset()
buffer.insert([11, 0], '...')
expect(markerChangedHandler).toHaveBeenCalled()
expect(markerChangedHandler.argsForCall[0][0]).toEqual {
oldHeadScreenPosition: [8, 20]
oldHeadBufferPosition: [11, 20]
newHeadScreenPosition: [8, 23]
newHeadBufferPosition: [11, 23]
oldTailScreenPosition: [5, 4]
oldTailBufferPosition: [8, 4]
newTailScreenPosition: [5, 4]
newTailBufferPosition: [8, 4]
textChanged: true
isValid: true
}
markerChangedHandler.reset()
displayBuffer.unfoldBufferRow(4)
expect(markerChangedHandler).toHaveBeenCalled()
expect(markerChangedHandler.argsForCall[0][0]).toEqual {
oldHeadScreenPosition: [8, 23]
oldHeadBufferPosition: [11, 23]
newHeadScreenPosition: [11, 23]
newHeadBufferPosition: [11, 23]
oldTailScreenPosition: [5, 4]
oldTailBufferPosition: [8, 4]
newTailScreenPosition: [8, 4]
newTailBufferPosition: [8, 4]
textChanged: false
isValid: true
}
markerChangedHandler.reset()
displayBuffer.createFold(4, 7)
expect(markerChangedHandler).toHaveBeenCalled()
expect(markerChangedHandler.argsForCall[0][0]).toEqual {
oldHeadScreenPosition: [11, 23]
oldHeadBufferPosition: [11, 23]
newHeadScreenPosition: [8, 23]
newHeadBufferPosition: [11, 23]
oldTailScreenPosition: [8, 4]
oldTailBufferPosition: [8, 4]
newTailScreenPosition: [5, 4]
newTailBufferPosition: [8, 4]
textChanged: false
isValid: true
}
it "triggers the 'changed' event whenever the marker tail's position changes in the buffer or on screen", ->
marker.setTailScreenPosition([8, 20])
expect(markerChangedHandler).toHaveBeenCalled()
expect(markerChangedHandler.argsForCall[0][0]).toEqual {
oldHeadScreenPosition: [5, 10]
oldHeadBufferPosition: [8, 10]
newHeadScreenPosition: [5, 10]
newHeadBufferPosition: [8, 10]
oldTailScreenPosition: [5, 4]
oldTailBufferPosition: [8, 4]
newTailScreenPosition: [8, 20]
newTailBufferPosition: [11, 20]
textChanged: false
isValid: true
}
markerChangedHandler.reset()
buffer.insert([11, 0], '...')
expect(markerChangedHandler).toHaveBeenCalled()
expect(markerChangedHandler.argsForCall[0][0]).toEqual {
oldHeadScreenPosition: [5, 10]
oldHeadBufferPosition: [8, 10]
newHeadScreenPosition: [5, 10]
newHeadBufferPosition: [8, 10]
oldTailScreenPosition: [8, 20]
oldTailBufferPosition: [11, 20]
newTailScreenPosition: [8, 23]
newTailBufferPosition: [11, 23]
textChanged: true
isValid: true
}
it "triggers the 'changed' event whenever the marker is invalidated or revalidated", ->
buffer.deleteRow(8)
expect(markerChangedHandler).toHaveBeenCalled()
expect(markerChangedHandler.argsForCall[0][0]).toEqual {
oldHeadScreenPosition: [5, 10]
oldHeadBufferPosition: [8, 10]
newHeadScreenPosition: [5, 0]
newHeadBufferPosition: [8, 0]
oldTailScreenPosition: [5, 4]
oldTailBufferPosition: [8, 4]
newTailScreenPosition: [5, 0]
newTailBufferPosition: [8, 0]
textChanged: true
isValid: false
}
markerChangedHandler.reset()
buffer.undo()
expect(markerChangedHandler).toHaveBeenCalled()
expect(markerChangedHandler.argsForCall[0][0]).toEqual {
oldHeadScreenPosition: [5, 0]
oldHeadBufferPosition: [8, 0]
newHeadScreenPosition: [5, 10]
newHeadBufferPosition: [8, 10]
oldTailScreenPosition: [5, 0]
oldTailBufferPosition: [8, 0]
newTailScreenPosition: [5, 4]
newTailBufferPosition: [8, 4]
textChanged: true
isValid: true
}
it "does not call the callback for screen changes that don't change the position of the marker", ->
displayBuffer.createFold(10, 11)
expect(markerChangedHandler).not.toHaveBeenCalled()
it "updates markers before emitting buffer change events, but does not notify their observers until the change event", ->
marker2 = displayBuffer.markBufferRange([[8, 1], [8, 1]])
marker2.on 'changed', marker2ChangedHandler = jasmine.createSpy("marker2ChangedHandler")
displayBuffer.on 'changed', changeHandler = jasmine.createSpy("changeHandler").andCallFake -> onDisplayBufferChange()
# New change ----
onDisplayBufferChange = ->
# calls change handler first
expect(markerChangedHandler).not.toHaveBeenCalled()
expect(marker2ChangedHandler).not.toHaveBeenCalled()
# but still updates the markers
expect(marker.getScreenRange()).toEqual [[5, 7], [5, 13]]
expect(marker.getHeadScreenPosition()).toEqual [5, 13]
expect(marker.getTailScreenPosition()).toEqual [5, 7]
expect(marker2.isValid()).toBeFalsy()
buffer.setTextInRange([[8, 0], [8, 2]], ".....")
expect(changeHandler).toHaveBeenCalled()
expect(markerChangedHandler).toHaveBeenCalled()
expect(marker2ChangedHandler).toHaveBeenCalled()
# Undo change ----
changeHandler.reset()
markerChangedHandler.reset()
marker2ChangedHandler.reset()
marker3 = displayBuffer.markBufferRange([[8, 1], [8, 2]])
marker3.on 'changed', marker3ChangedHandler = jasmine.createSpy("marker3ChangedHandler")
onDisplayBufferChange = ->
# calls change handler first
expect(markerChangedHandler).not.toHaveBeenCalled()
expect(marker2ChangedHandler).not.toHaveBeenCalled()
expect(marker3ChangedHandler).not.toHaveBeenCalled()
# but still updates the markers
expect(marker.getScreenRange()).toEqual [[5, 4], [5, 10]]
expect(marker.getHeadScreenPosition()).toEqual [5, 10]
expect(marker.getTailScreenPosition()).toEqual [5, 4]
expect(marker2.isValid()).toBeTruthy()
expect(marker3.isValid()).toBeFalsy()
buffer.undo()
expect(changeHandler).toHaveBeenCalled()
expect(markerChangedHandler).toHaveBeenCalled()
expect(marker2ChangedHandler).toHaveBeenCalled()
expect(marker3ChangedHandler).toHaveBeenCalled()
# Redo change ----
changeHandler.reset()
markerChangedHandler.reset()
marker2ChangedHandler.reset()
marker3ChangedHandler.reset()
onDisplayBufferChange = ->
# calls change handler first
expect(markerChangedHandler).not.toHaveBeenCalled()
expect(marker2ChangedHandler).not.toHaveBeenCalled()
expect(marker3ChangedHandler).not.toHaveBeenCalled()
# but still updates the markers
expect(marker.getScreenRange()).toEqual [[5, 7], [5, 13]]
expect(marker.getHeadScreenPosition()).toEqual [5, 13]
expect(marker.getTailScreenPosition()).toEqual [5, 7]
expect(marker2.isValid()).toBeFalsy()
expect(marker3.isValid()).toBeTruthy()
buffer.redo()
expect(changeHandler).toHaveBeenCalled()
expect(markerChangedHandler).toHaveBeenCalled()
expect(marker2ChangedHandler).toHaveBeenCalled()
expect(marker3ChangedHandler).toHaveBeenCalled()
it "updates the position of markers before emitting change events that aren't caused by a buffer change", ->
displayBuffer.on 'changed', changeHandler = jasmine.createSpy("changeHandler").andCallFake ->
# calls change handler first
expect(markerChangedHandler).not.toHaveBeenCalled()
# but still updates the markers
expect(marker.getScreenRange()).toEqual [[8, 4], [8, 10]]
expect(marker.getHeadScreenPosition()).toEqual [8, 10]
expect(marker.getTailScreenPosition()).toEqual [8, 4]
displayBuffer.unfoldBufferRow(4)
expect(changeHandler).toHaveBeenCalled()
expect(markerChangedHandler).toHaveBeenCalled()
describe "::findMarkers(attributes)", ->
it "allows the startBufferRow and endBufferRow to be specified", ->
marker1 = displayBuffer.markBufferRange([[0, 0], [3, 0]], class: 'a')
marker2 = displayBuffer.markBufferRange([[0, 0], [5, 0]], class: 'a')
marker3 = displayBuffer.markBufferRange([[9, 0], [10, 0]], class: 'b')
expect(displayBuffer.findMarkers(class: 'a', startBufferRow: 0)).toEqual [marker2, marker1]
expect(displayBuffer.findMarkers(class: 'a', startBufferRow: 0, endBufferRow: 3)).toEqual [marker1]
expect(displayBuffer.findMarkers(endBufferRow: 10)).toEqual [marker3]
describe "marker destruction", ->
it "allows markers to be destroyed", ->
marker = displayBuffer.markScreenRange([[5, 4], [5, 10]])
marker.destroy()
expect(marker.isValid()).toBeFalsy()
expect(displayBuffer.getMarker(marker.id)).toBeUndefined()
it "emits 'destroyed' events when markers are destroyed", ->
destroyedHandler = jasmine.createSpy("destroyedHandler")
marker = displayBuffer.markScreenRange([[5, 4], [5, 10]])
marker.on 'destroyed', destroyedHandler
marker.destroy()
expect(destroyedHandler).toHaveBeenCalled()
destroyedHandler.reset()
marker2 = displayBuffer.markScreenRange([[5, 4], [5, 10]])
marker2.on 'destroyed', destroyedHandler
buffer.getMarker(marker2.id).destroy()
expect(destroyedHandler).toHaveBeenCalled()
describe "DisplayBufferMarker::copy(attributes)", ->
it "creates a copy of the marker with the given attributes merged in", ->
initialMarkerCount = displayBuffer.getMarkerCount()
marker1 = displayBuffer.markScreenRange([[5, 4], [5, 10]], a: 1, b: 2)
expect(displayBuffer.getMarkerCount()).toBe initialMarkerCount + 1
marker2 = marker1.copy(b: 3)
expect(marker2.getBufferRange()).toEqual marker1.getBufferRange()
expect(displayBuffer.getMarkerCount()).toBe initialMarkerCount + 2
expect(marker1.getAttributes()).toEqual a: 1, b: 2
expect(marker2.getAttributes()).toEqual a: 1, b: 3
describe "DisplayBufferMarker::getPixelRange()", ->
it "returns the start and end positions of the marker based on the line height and character widths assigned to the DisplayBuffer", ->
marker = displayBuffer.markScreenRange([[5, 10], [6, 4]])
displayBuffer.setLineHeight(20)
displayBuffer.setDefaultCharWidth(10)
displayBuffer.setScopedCharWidths(["source.js", "keyword.control.js"], r: 11, e: 11, t: 11, u: 11, n: 11)
{start, end} = marker.getPixelRange()
expect(start.top).toBe 5 * 20
expect(start.left).toBe (4 * 10) + (6 * 11)
describe "::setScrollTop", ->
beforeEach ->
displayBuffer.manageScrollPosition = true
displayBuffer.setLineHeight(10)
it "disallows negative values", ->
displayBuffer.setHeight(displayBuffer.getScrollHeight() + 100)
expect(displayBuffer.setScrollTop(-10)).toBe 0
expect(displayBuffer.getScrollTop()).toBe 0
it "disallows values that would make ::getScrollBottom() exceed ::getScrollHeight()", ->
displayBuffer.setHeight(50)
maxScrollTop = displayBuffer.getScrollHeight() - displayBuffer.getHeight()
expect(displayBuffer.setScrollTop(maxScrollTop)).toBe maxScrollTop
expect(displayBuffer.getScrollTop()).toBe maxScrollTop
expect(displayBuffer.setScrollTop(maxScrollTop + 50)).toBe maxScrollTop
expect(displayBuffer.getScrollTop()).toBe maxScrollTop
describe "::setScrollLeft", ->
beforeEach ->
displayBuffer.manageScrollPosition = true
displayBuffer.setLineHeight(10)
displayBuffer.setDefaultCharWidth(10)
it "disallows negative values", ->
displayBuffer.setWidth(displayBuffer.getScrollWidth() + 100)
expect(displayBuffer.setScrollLeft(-10)).toBe 0
expect(displayBuffer.getScrollLeft()).toBe 0
it "disallows values that would make ::getScrollRight() exceed ::getScrollWidth()", ->
displayBuffer.setWidth(50)
maxScrollLeft = displayBuffer.getScrollWidth() - displayBuffer.getWidth()
expect(displayBuffer.setScrollLeft(maxScrollLeft)).toBe maxScrollLeft
expect(displayBuffer.getScrollLeft()).toBe maxScrollLeft
expect(displayBuffer.setScrollLeft(maxScrollLeft + 50)).toBe maxScrollLeft
expect(displayBuffer.getScrollLeft()).toBe maxScrollLeft
describe "::scrollToScreenPosition(position)", ->
it "sets the scroll top and scroll left so the given screen position is in view", ->
displayBuffer.manageScrollPosition = true
displayBuffer.setLineHeight(10)
displayBuffer.setDefaultCharWidth(10)
displayBuffer.setHorizontalScrollbarHeight(0)
displayBuffer.setHeight(50)
displayBuffer.setWidth(50)
maxScrollTop = displayBuffer.getScrollHeight() - displayBuffer.getHeight()
displayBuffer.scrollToScreenPosition([8, 20])
expect(displayBuffer.getScrollBottom()).toBe (9 + displayBuffer.getVerticalScrollMargin()) * 10
expect(displayBuffer.getScrollRight()).toBe (20 + displayBuffer.getHorizontalScrollMargin()) * 10