Implement data driven test framework

- Add run_test(): Test a function and verify its output
- Add run_test_group(): Execute a test batch
- Add serialise_value(): Serialise a Lua value into the Lua syntax
- Add file_save() helper function
- Add NaN comparison support to compare_values()

3 files changed, 158 insertions, 29 deletions

diff --git a/tests/bench.lua b/tests/bench.lua
index b5b1a77..847365b 100755
--- a/tests/bench.lua
+++ b/tests/bench.lua
@@ -3,11 +3,11 @@
 -- Simple JSON benchmark.
 --
 -- Your Mileage May Vary.
+--
+-- Mark Pulford <mark@kyne.com.au>
 
 require "common"
 local json = require "cjson"
---local json = require "json"
---local json = require "dkjson"
 
 function bench_file(filename)
     local data_json = file_load(filename)
@@ -28,12 +28,11 @@ function bench_file(filename)
     return benchmark(tests, 5000, 5)
 end
 
-i = 1
-while arg[i] do
-    local results = {}
-    results[arg[i]] = bench_file(arg[i])
-    dump_value(results)
-    i = i + 1
+for i = 1, #arg do
+    local results = bench_file(arg[i])
+    for k, v in pairs(results) do
+        print(string.format("%s: %s: %d", arg[i], k, v))
+    end
 end
 
 -- vi:ai et sw=4 ts=4:
diff --git a/tests/common.lua b/tests/common.lua
index 219de3f..9a7ed19 100644
--- a/tests/common.lua
+++ b/tests/common.lua
@@ -1,31 +1,94 @@
 require "cjson"
 require "posix"
 
-function dump_value(value, indent)
-    if indent == nil then
-        indent = ""
+-- Misc routines to assist with CJSON testing
+--
+-- Mark Pulford <mark@kyne.com.au>
+
+-- Determine with a Lua table can be treated as an array.
+-- Explicitly returns "not an array" for very sparse arrays.
+-- Returns:
+-- -1   Not an array
+-- 0    Empty table
+-- >0   Highest index in the array
+function is_array(table)
+    local max = 0
+    local count = 0
+    for k, v in pairs(table) do
+        if type(k) == "number" then
+            if k > max then max = k end
+            count = count + 1
+        else
+            return -1
+        end
+    end
+    if max > count * 2 then
+        return -1
     end
 
-    if value == cjson.null then
-        value = "<cjson.null>"
+    return max
+end
+
+function serialise_table(value, indent)
+    local spacing, spacing2, indent2
+    if indent then 
+        spacing = "\n" .. indent
+        spacing2 = spacing .. "  "
+        indent2 = indent .. "  "
+    else
+        spacing, spacing2, indent2 = " ", " ", false
     end
 
-    if type(value) == "string" or type(value) == "number" or
-       type(value) == "boolean" then
-        print(indent .. tostring(value))
-    elseif type(value) == "table" then
-        local count = 0
-        for k, v in pairs(value) do
-            dump_value(v, indent .. k .. ":  ")
-            count = count + 1
+    local max = is_array(value)
+
+    local comma = false
+    local fragment = { "{" .. spacing2 }
+    if max > 0 then
+        -- Serialise array
+        for i = 1, max do
+            if comma then
+                table.insert(fragment, "," .. spacing2)
+            end
+            table.insert(fragment, serialise_value(value[i], indent2))
+            comma = true
         end
-        if count == 0 then
-            print(indent .. ": <empty>")
+    elseif max < 0 then
+        -- Serialise table
+        for k, v in pairs(value) do
+            if comma then
+                table.insert(fragment, "," .. spacing2)
+            end
+            table.insert(fragment, string.format(
+                "[%s] = %s", serialise_value(k, indent2),
+                             serialise_value(v, indent2))
+            )
+            comma = true
         end
+    end
+    table.insert(fragment, spacing .. "}")
+
+    return table.concat(fragment)
+end
+
+function serialise_value(value, indent)
+    if indent == nil then indent = "" end
+
+    if value == cjson.null then
+        return "cjson.null"
+    elseif type(value) == "string" then
+        return string.format("%q", value)
+    elseif type(value) == "nil" or type(value) == "number" or
+           type(value) == "boolean" then
+        return tostring(value)
+    elseif type(value) == "table" then
+        return serialise_table(value, indent)
     else
-        print(indent .. "<" .. type(value) .. ">")
+        return "\"<" .. type(value) .. ">\""
     end
+end
 
+function dump_value(value)
+    print(serialise_value(value))
 end
 
 function file_load(filename)
@@ -39,6 +102,15 @@ function file_load(filename)
     return data
 end
 
+function file_save(filename, data)
+    local file, err = io.open(filename, "w")
+    if file == nil then
+        error("Unable to write " .. filename)
+    end
+    file:write(data)
+    file:close()
+end
+
 function gettimeofday()
     local tv_sec, tv_usec = posix.gettimeofday()
 
@@ -82,29 +154,83 @@ function compare_values(val1, val2)
     if type1 ~= type2 then
         return false
     end
+
+    -- Check for NaN
+    if type1 == "number" and val1 ~= val1 and val2 ~= val2 then
+        return true
+    end
+
     if type1 ~= "table" then
         return val1 == val2
     end
-    local val1_keys = {}
-    -- Note all the keys in val1 need to be checked
+
+    -- check_keys stores all the keys that must be checked in val2
+    local check_keys = {}
     for k, _ in pairs(val1) do
         check_keys[k] = true
     end
+
     for k, v in pairs(val2) do
         if not check_keys[k] then
-            -- Key didn't exist in val1
             return false
         end
-        if not compare_value(val1[k], val2[k]) then
+
+        if not compare_values(val1[k], val2[k]) then
             return false
         end
+
         check_keys[k] = nil
     end
     for k, _ in pairs(check_keys) do
-        -- Not the same if any keys left to check
+        -- Not the same if any keys from val1 were not found in val2
         return false
     end
     return true
 end
 
+function run_test(testname, func, input, should_work, output)
+    local function status_line(name, status, value)
+        local statusmap = { [true] = ":success", [false] = ":error" }
+        if status ~= nil then
+            name = name .. statusmap[status]
+        end
+        print(string.format("[%s] %s", name, serialise_value(value, false)))
+    end
+
+    local result = { pcall(func, unpack(input)) }
+    local success = table.remove(result, 1)
+
+    local correct = false
+    if success == should_work and compare_values(result, output) then
+        correct = true
+    end
+
+    local teststatus = { [true] = "PASS", [false] = "FAIL" }
+    print("==> Test " .. testname .. ": " .. teststatus[correct])
+
+    status_line("Input", nil, input)
+    if not correct then
+        status_line("Expected", should_work, output)
+    end
+    status_line("Received", success, result)
+    print()
+
+    return correct, result
+end
+
+function run_test_group(testgroup, tests)
+    for k, v in ipairs(tests) do
+        if type(v) == "function" then
+            -- Useful for changing configuration during a batch
+            msg = v()
+            print(string.format("==> Config %s [%d]: %s", testgroup, k, msg))
+            print()
+        elseif type(v) == "table" then
+            run_test(testgroup .. " [" .. k .. "]", unpack(v))
+        else
+            error("Testgroup can only contain functions and tables")
+        end
+    end
+end
+
 -- vi:ai et sw=4 ts=4:
diff --git a/tests/test.lua b/tests/test.lua
index 3c8c404..51f29c4 100755
--- a/tests/test.lua
+++ b/tests/test.lua
@@ -1,5 +1,9 @@
 #!/usr/bin/env lua
 
+-- CJSON tests
+--
+-- Mark Pulford <mark@kyne.com.au>
+
 require "common"
 local json = require "cjson"