neyuki 0.6.2

A small Lua-like scripting language implemented in Rust
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-- Tests for `repeat ... until` loops, whose condition sees the body's locals.

-- 1. The condition reads a local declared in the body
local n = 0
repeat
    n = n + 1
    local y = n
until y >= 3
assert(n == 3, "until sees body local")

-- 2. A body local shadows an outer one inside the condition only
local stop = true
local count = 0
repeat
    count = count + 1
    local stop = count == 4
until stop
assert(count == 4, "until uses the shadowing body local")
assert(stop == true, "outer local untouched after loop")

-- 3. The body local is out of scope after the loop
local done_value = 0
repeat
    local done_value = 99
until done_value == 99
assert(done_value == 0, "body local does not leak past until")

-- 4. `continue` still jumps to the condition with the body local set
local seen = {}
local i = 0
repeat
    i = i + 1
    local last = i >= 5
    if i % 2 == 0 then
        continue
    end
    seen[#seen + 1] = i
until last
assert(i == 5, "continue loop ran to the end")
assert(#seen == 3 and seen[1] == 1 and seen[2] == 3 and seen[3] == 5, "continue skipped even values")

-- 5. A closure in the condition captures this iteration's local
local fns = {}
local k = 0
repeat
    k = k + 1
    local v = k * 10
until (function()
    fns[#fns + 1] = function() return v end
    return v >= 30
end)()
assert(#fns == 3, "condition closure ran each iteration")
assert(fns[1]() == 10 and fns[2]() == 20 and fns[3]() == 30, "condition closures keep their own locals")

-- 6. Nested repeat loops each see their own body locals
local outer_runs = 0
local inner_total = 0
repeat
    outer_runs = outer_runs + 1
    local j = 0
    repeat
        j = j + 1
        local inner_done = j == outer_runs
        inner_total = inner_total + 1
    until inner_done
    local outer_done = outer_runs == 3
until outer_done
assert(outer_runs == 3 and inner_total == 6, "nested repeat loops scope their locals")

print("repeat_until tests passed")