From 5f2d60f70e5fb5400d6136cfc0f57108095ec826 Mon Sep 17 00:00:00 2001
From: Henrik Ilgen <henrik@ilgen.dev>
Date: Wed, 11 Dec 2024 10:54:12 +0100
Subject: [PATCH] Basic documentation and a test for :zip

---
 README.md                 | 14 ++++++++++++--
 docs/index.md             | 12 ++++++++++++
 test/intermediate/zip.lua | 12 ++++++++++++
 3 files changed, 36 insertions(+), 2 deletions(-)
 create mode 100644 test/intermediate/zip.lua

diff --git a/README.md b/README.md
index aa1d666..599d501 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # lazylualinq
 
-[![tests](https://github.com/Henkoglobin/lazylualinq/actions/workflows/test-and-publish.yml/badge.svg)](https://github.com/Henkoglobin/lazylualinq/actions/workflows/test-and-publish.yml) [![luarocks](https://img.shields.io/luarocks/v/henkoglobin/lazylualinq?style=plastic)](https://luarocks.org/modules/henkoglobin/lazylualinq)
+[![tests](https://github.com/Henkoglobin/lazylualinq/actions/workflows/test-and-publish.yml/badge.svg)](https://github.com/Henkoglobin/lazylualinq/actions/workflows/test-and-publish.yml) [![luarocks](https://img.shields.io/luarocks/v/henkoglobin/lazylualinq?style=plastic)](https://luarocks.org/modules/henkoglobin/lazylualinq) [![pages-build-deployment](https://github.com/Henkoglobin/lazylualinq/actions/workflows/pages/pages-build-deployment/badge.svg?branch=main)](https://henkoglobin.github.io/lazylualinq/)
 
 LazyLuaLinq provides a simple, _lazy_ implementation of linq-like functions for Lua. With LazyLuaLinq, you can implement data transformation in elegant, expressive _queries_ akin to SQL:
 
@@ -401,4 +401,14 @@ local linq = require("lazylualinq")
         setfenv(func, env)
         return func
     end)
-```
\ No newline at end of file
+```
+
+# Dependencies and running tests
+
+In order to develop lazylualinq, you should install the test dependencies:
+
+```bash
+sudo luarocks test --prepare
+```
+
+Then, you can run the tests using `luarocks test`.
\ No newline at end of file
diff --git a/docs/index.md b/docs/index.md
index b9362b7..253b423 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -238,6 +238,18 @@ local seq = linq { "a", "b", "c" }:take(2)
 ```
 
 ## `linq:zip(other, resultSelector)`
+
+`zip` combines elements from the input and the `other` list, calling `resultSelector` for each pair of values. 
+It will only iterate the input sequences as long as the _shorter_ of both sequences yields values.
+
+`resultSelector` has the following signature: `function(leftValue, leftKey, rightValue, rightKey)`.
+
+```lua
+local seq = linq { "foo", "egg", "hello" }
+    :zip(linq{ "bar", "spam" }, function(l, _, r) return l .. r end)
+-- seq is now equivalent to linq { "foobar", "eggspam" }
+```
+
 ## `linq:defaultIfEmpty(defaultValue, defaultIndex)`
 ## `linq:reindex()`
 ## `linq:nonNil()`
diff --git a/test/intermediate/zip.lua b/test/intermediate/zip.lua
new file mode 100644
index 0000000..5df985b
--- /dev/null
+++ b/test/intermediate/zip.lua
@@ -0,0 +1,12 @@
+describe("intermediate operator #zip", function()
+    local linq = require("lazylualinq")
+
+    it("only iterates until one sequence runs out of items", function()
+        local iterator = linq { "foo", "egg", "hello" }
+            :zip(linq{ "bar", "spam" }, function(l, _, r) return l .. r end)
+            :getIterator()
+
+        assert.is_same({"foobar", 1}, { iterator() })
+        assert.is_same({"eggspam", 2}, { iterator() })
+    end)
+end)
\ No newline at end of file