tasks.json and launch.json generation for Tundra2

vscode.lua

module(..., package.seeall)

local native  = require "tundra.native"
local nodegen = require "tundra.nodegen"
local path    = require "tundra.path"
local util    = require "tundra.util"
local ide_com = require "tundra.ide.ide-common"

local project_types = ide_com.project_types

local vscode_generator = {}
vscode_generator.__index = vscode_generator

local function to_json(obj, f, indent)
  indent = indent or ""

  if type(obj) ~= "table" then
    if type(obj) == "string" then
      f:write('"')
      f:write(obj)
      f:write('"')
    else
      f:write(tostring(obj)) -- boolean, number
    end
  else
    -- table or array?
    if obj[1] then
      -- array
      local indent2 = indent .. "  "
      f:write("[\n", indent2)
      for i, v in ipairs(obj) do
        if 1 < i then
          f:write(",\n", indent2)
        end
        to_json(v, f, indent2)
      end
      f:write("\n", indent, "]")
    else
      local indent2 = indent .. "  "
      f:write(indent, "{\n", indent2)
      local k, v = next(obj)
      if k then
        to_json(k, f, indent2)
        f:write(": ")
        to_json(v, f, indent2)
        k, v = next(obj, k)
        while k do
          f:write(",\n", indent2)
          to_json(k, f, indent2)
          f:write(": ")
          to_json(v, f, indent2)
          k, v = next(obj, k)
        end
      end
      f:write("\n", indent, "}")
    end
  end

end

function vscode_generator:generate_files(ngen, config_tuples, raw_nodes, env, default_nodes, hints, ide_script)
  assert(config_tuples and #config_tuples > 0)

  local units = util.filter(raw_nodes, function (u)
    return u.Decl.Name and project_types[u.Keyword]
  end)

  -- DAG nodes have:
  --   inputs
  --   action
  --   annotation
  --   pass
  --   aux_outputs
  --   expensive
  --   overwrite_outputs
  --   deps
  --   src_env
  --   env
  --   outputs

  local tasks = {}
  local configurations = {}

  for _, unit in ipairs(units) do
    local decl = unit.Decl
    local dag_nodes = assert(decl.__DagNodes, "no dag nodes for " .. decl.Name)
    for build_id, dag_node in pairs(dag_nodes) do
      local label = decl.Name .. " (" .. build_id .. ")"

      tasks[#tasks + 1] = {
        type = "process",
        label = label,
        command = "tundra2.exe",
        args = {
          build_id,
          decl.Name
        },
        problemMatcher = {
          "$msCompile"
        },
        group = {
          kind = "build",
          isDefault = default_nodes[dag_node] or false
        }
      }

      for _, output in ipairs(dag_node.outputs) do
        if output:match("%.exe") then
          configurations[#configurations + 1] = {
            name = label,
            type = "cppvsdbg",
            request = "launch",
            program = "${workspaceFolder}/" .. output:gsub("\\", "/"),
            cwd = "${workspaceFolder}/t2-output/" .. build_id,
            preLaunchTask = label,
            visualizerFile = "${workspaceFolder}/game.natvis",
            console = "integratedTerminal"
          }
          break
        end
      end
    end
  end

  local tasks_json = assert(io.open(".vscode/tasks.json.tmp", 'wb'))
  to_json({
    ["//"]= {"This file was generated by a tool. DO NOT EDIT.", "tundra2 -g vscode"},
    version = "2.0.0",
    tasks = tasks
  }, tasks_json)
  tasks_json:close()
  ide_com.replace_if_changed(".vscode/tasks.json.tmp", ".vscode/tasks.json")

  local launch_json = assert(io.open(".vscode/launch.json.tmp", 'wb'))
  to_json({
    ["//"]= {"This file was generated by a tool. DO NOT EDIT.", "tundra2 -g vscode"},
    version = "0.2.0",
    configurations = configurations
  }, launch_json)
  launch_json:close()
  ide_com.replace_if_changed(".vscode/launch.json.tmp", ".vscode/launch.json")
end

-- https://github.com/deplinenoise/tundra/blob/e48e03bbd8a193889337d25b42cfbd64c64c1c33/scripts/tundra/nodegen.lua#L816-L822
nodegen.set_ide_backend(function(...)
  local state = setmetatable({}, vscode_generator)
  state:generate_files(...)
end)