Trans.nvim/lua/test/buffer_spec.lua

local Trans = require 'Trans'
local node = Trans.util.node
local i, t, pr, f = node.item, node.text, node.prompt, node.format

---@param func fun(buffer: TransBuffer)
---@return fun()
local function with_buffer(func)
    return function()
        local buffer = Trans.buffer.new()
        func(buffer)
        buffer:destroy()
    end
end


describe('buffer:setline()', function()
    it('can accept one index linenr as second arg', with_buffer(function(buffer)
        buffer:setline({
            i { 'hello ' },
            i { 'world' },
        }, 1)
        assert.are.equal(buffer[1], 'hello world')
    end))

    it('when no second arg, it will append line', with_buffer(function(buffer)
        buffer[1] = 'hello'
        buffer:setline 'world'

        assert.are.equal(buffer[2], 'world')
    end))

    describe('and buffer[i]', function()
        it('can accept a string as first arg', with_buffer(function(buffer)
            buffer:setline 'hello world'
            buffer[2] = 'hello world'
            assert.are.equal(buffer[1], 'hello world')
            assert.are.equal(buffer[2], 'hello world')
        end))

        it('can accept a node as first arg', with_buffer(function(buffer)
            buffer:setline(i { 'hello world' })
            buffer[2] = i { 'hello world' }
            assert.are.equal(buffer[1], 'hello world')
            assert.are.equal(buffer[2], 'hello world')
        end))

        it('can accept a node list as first arg', with_buffer(function(buffer)
            buffer:setline {
                i { 'hello ' },
                i { 'world' },
            }

            buffer[2] = {
                i { 'hello ' },
                i { 'world' },
            }

            assert.are.equal(buffer[1], 'hello world')
            assert.are.equal(buffer[2], 'hello world')
        end))

        it(' will fill with empty line if accept linenr more than line_count', with_buffer(function(buffer)
            buffer:setline('hello world', 3)
            buffer[4] = 'hello world'
            assert.are.equal(buffer[1], '')
            assert.are.equal(buffer[2], '')
            assert.are.equal(buffer[3], 'hello world')
            assert.are.equal(buffer[4], 'hello world')

            buffer:wipe()

            buffer[1] = i { 'test' }
            buffer[3] = 'hello world'
            assert.are.equal(buffer[1], 'test')
            assert.are.equal(buffer[2], '')
            assert.are.equal(buffer[3], 'hello world')
        end))
    end)
end)
-- TODO :Add node test