From 5a3e9d0e27de677206b45168f92d5bf3fdb6dfb0 Mon Sep 17 00:00:00 2001
From: Jon Michael Aanes <jonjmaa@gmail.com>
Date: Wed, 5 Apr 2017 13:10:23 +0200
Subject: [PATCH] Improved sorting of tables.

---
 pretty.lua           | 34 ++++++++++++++++++++++++----------
 test/test_pretty.lua | 12 +++++++++++-
 2 files changed, 35 insertions(+), 11 deletions(-)

diff --git a/pretty.lua b/pretty.lua
index 3ca5aa6..a514ea5 100644
--- a/pretty.lua
+++ b/pretty.lua
@@ -37,7 +37,17 @@ local SINGLE_LINE_SEQ_MAX_ELEMENTS = 10
 local SINGLE_LINE_MAP_MAX_ELEMENTS = 5
 local NR_CHARS_IN_LONG_STRING      = 40
 
-local TYPE_SORT_ORDER = {
+local KEY_TYPE_SORT_ORDER = {
+    ['number']   = 0,
+    ['string']   = 1,
+    ['boolean']  = 2,
+    ['table']    = 3,
+    ['userdata'] = 4,
+    ['thread']   = 5,
+    ['function'] = 6,
+}
+
+local VALUE_TYPE_SORT_ORDER = {
     ['nil']      = 0,
     ['boolean']  = 1,
     ['number']   = 2,
@@ -118,23 +128,27 @@ local function compare_key_value_pairs (a, b)
     local type_value_a, type_value_b = type(a[2]), type(b[2])
 
     -- Tons of compare
-    if (type_key_a == 'string' and type_key_b == 'string') then
-        return alphanum_compare_strings(a[1], b[1])
+    if (1 == (type_key_a == 'number' and 1 or 0) + (type_key_b == 'number' and 1 or 0)) then
+        return type_key_a == 'number'
     elseif (type_key_a == 'number' and type_key_b == 'number') then
         return a[1] < b[1]
-    else
-        return TYPE_SORT_ORDER[type_value_a] < TYPE_SORT_ORDER[type_value_b]
+    elseif (type_value_a ~= type_value_b) then
+        return VALUE_TYPE_SORT_ORDER[type_value_a] < VALUE_TYPE_SORT_ORDER[type_value_b]
+    elseif (type_key_a == 'string' and type_key_b == 'string') then
+        return alphanum_compare_strings(a[1], b[1])
+    elseif (type_key_a ~= type_key_b) then
+        return KEY_TYPE_SORT_ORDER[type_value_a] < KEY_TYPE_SORT_ORDER[type_value_b]
     end
 end
 
 local function get_key_value_pairs_in_proper_order (t)
     -- Generates a sequence of key value pairs, in proper order.
     -- Proper order is:
-    -- 1. By value type: as defined by the TYPE_SORT_ORDER in the top.
-    -- 2. By key type:  TODO: Implement this.
-    -- 2.1.  Numbers
-    -- 2.2.  Strings in alphanumeric order
-    -- 2.3.  Other wierdness.
+    -- 1. All integer keys are first, in order
+    -- 2. Then by value type, as defined in  VALUE_TYPE_SORT_ORDER in the top.
+    -- 3. Then by key type.
+    -- 3.1. String in alphanumeric order
+    -- 3.2. Other wierdness.
 
     local key_value_pairs = {}
 
diff --git a/test/test_pretty.lua b/test/test_pretty.lua
index 7bf2bd6..422fc29 100644
--- a/test/test_pretty.lua
+++ b/test/test_pretty.lua
@@ -284,7 +284,7 @@ format_test {
 
 format_test {
     input  = { [true] = 1, [1] = false },
-    expect = '{\n\t[true] = 1,\n\t[1]    = false\n}',
+    expect = '{\n\t[1]    = false,\n\t[true] = 1\n}',
 }
 
 format_test {
@@ -361,6 +361,16 @@ format_test {
     expect = '{ {}, true, false, 5 }',
 }
 
+format_test {
+    input  = { [1] = {}, [2] = {}, [3] = {}, ['down_info'] = {}, ['up_info'] = {} },
+    expect = '{\n\t[1]           = {},\n\t[2]           = {},\n\t[3]           = {},\n\t[\'down_info\'] = {},\n\t[\'up_info\']   = {}\n}',
+}
+
+format_test {
+    input  = { 'hello', 123, {}, true },
+    expect = '{ \'hello\', 123, {}, true }',
+}
+
 -- TODO: Add more tests for sorting.
 
 --------------------------------------------------------------------------------