From 6e79158f28c7a125497fbba0c66890bb853ed4e0 Mon Sep 17 00:00:00 2001
From: Jakub Sobolewski <jakub.sobolewski@appsilon.com>
Date: Sun, 19 Jan 2025 20:41:16 +0000
Subject: [PATCH] =?UTF-8?q?test:=20:test=5Ftube::x:=20Create=20specificati?=
 =?UTF-8?q?on=20for=20the=20registry=20=E2=80=93=20interface=20for=20persi?=
 =?UTF-8?q?stent=20storage?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- Add unit tests for an object that the app will interact with to store data to a persistent storage.
- I want to use a `registry` object to run operations on a `storage` object. The storage will be a CSV file, but it could as well be a database connection or a S3 bucket.
- This is an implementation detail of the app, it doesn't change the behavior of the app – tests are added to `tests/testthat/`, no changes in acceptance tests are needed.
---
 tests/testthat/test-registry.R | 155 +++++++++++++++++++++++++++++++++
 1 file changed, 155 insertions(+)
 create mode 100644 tests/testthat/test-registry.R

diff --git a/tests/testthat/test-registry.R b/tests/testthat/test-registry.R
new file mode 100644
index 0000000..c7a5cb2
--- /dev/null
+++ b/tests/testthat/test-registry.R
@@ -0,0 +1,155 @@
+box::use(
+  glue[glue],
+  testthat[...], # nolint
+  withr[with_tempdir],
+)
+
+box::use(
+  app / registry,
+  app / transaction,
+)
+
+# Fake storage
+create_storage <- function() {
+  .storage <- glue::glue("store_session_{as.numeric(Sys.time())}.csv")
+  write.csv(data.frame(amount = numeric()), .storage, row.names = FALSE)
+  .storage
+}
+
+describe("record", {
+  it("should record a transaction", {
+    with_tempdir({
+      # Arrange
+      .storage <- create_storage()
+      .registry <- registry$new(.storage)
+
+      # Act
+      .registry$record(transaction$new(100)) # nolint
+
+      # Assert
+      expect_equal(nrow(read.csv(.storage)), 1)
+    })
+  })
+
+  it("should record multiple transactions", {
+    with_tempdir({
+      # Arrange
+      .storage <- create_storage()
+      .registry <- registry$new(.storage)
+
+      # Act
+      .registry$record(transaction$new(100)) # nolint
+      .registry$record(transaction$new(100)) # nolint
+
+      # Assert
+      expect_equal(nrow(read.csv(.storage)), 2)
+    })
+  })
+
+  it("should throw an error if storage doesn't exist", {
+    # Arrange
+    with_tempdir({
+      .storage <- create_storage()
+    })
+
+    # Act, Assert
+    expect_error(
+      registry$new(.storage),
+      regexp = glue("File {.storage} does not exist"),
+      fixed = TRUE
+    )
+  })
+})
+
+describe("get_total_positive", {
+  it("should return the total of positive transactions", {
+    with_tempdir({
+      # Arrange
+      .storage <- create_storage()
+      .registry <- registry$new(.storage)
+
+      # Act
+      .registry$record(transaction$new(100)) # nolint
+      .registry$record(transaction$new(-100)) # nolint
+
+      # Assert
+      expect_equal(.registry$get_total_positive(), 100)
+    })
+  })
+
+  it("should return 0 if there are no transactions", {
+    with_tempdir({
+      # Arrange
+      .storage <- create_storage()
+      .registry <- registry$new(.storage)
+
+      # Act
+      result <- .registry$get_total_positive()
+
+      # Assert
+      expect_equal(result, 0)
+    })
+  })
+})
+
+describe("get_total_negative", {
+  it("should return the total of negative transactions", {
+    with_tempdir({
+      # Arrange
+      .storage <- create_storage()
+      .registry <- registry$new(.storage)
+
+      # Act
+      .registry$record(transaction$new(200)) # nolint
+      .registry$record(transaction$new(-100)) # nolint
+
+      # Assert
+      expect_equal(.registry$get_total_negative(), 100)
+    })
+  })
+
+  it("should return 0 if there are no transactions", {
+    with_tempdir({
+      # Arrange
+      .storage <- create_storage()
+      .registry <- registry$new(.storage)
+
+      # Act
+      result <- .registry$get_total_negative()
+
+      # Assert
+      expect_equal(result, 0)
+    })
+  })
+})
+
+describe("get_total", {
+  it("should return the total of all transactions", {
+    with_tempdir({
+      # Arrange
+      .storage <- create_storage()
+      .registry <- registry$new(.storage)
+
+      # Act
+      .registry$record(transaction$new(100)) # nolint
+      .registry$record(transaction$new(-100)) # nolint
+
+      # Assert
+      expect_equal(.registry$get_total(), 0)
+    })
+  })
+
+  it("should return 0 if there are no transactions", {
+    with_tempdir({
+      # Arrange
+      .storage <- create_storage()
+      .registry <- registry$new(.storage)
+
+      # Act
+      result <- .registry$get_total()
+
+      # Assert
+      expect_equal(result, 0)
+    })
+  })
+})