From 7e23cf94a648ea769e46b3eb9e9e7fa7a39ac983 Mon Sep 17 00:00:00 2001
From: Bert Peters <bert@bertptrs.nl>
Date: Tue, 2 Dec 2025 13:35:53 +0100
Subject: [PATCH] 2025 day 2 part 2 in Terraform

---
 2025/day02/README.md        |  29 +++++++++++
 2025/day02/range/main.tf    |   4 +-
 2025/day02/range2/main.tf   |   4 +-
 2025/day02/tests.tftest.hcl | 101 +++++++++++++++++++++++++++++++++++-
 4 files changed, 132 insertions(+), 6 deletions(-)
 create mode 100644 2025/day02/README.md

diff --git a/2025/day02/README.md b/2025/day02/README.md
new file mode 100644
index 0000000..5c438d6
--- /dev/null
+++ b/2025/day02/README.md
@@ -0,0 +1,29 @@
+## Day 02: Terraform
+
+The code assumes an input file at `../inputs/02.txt`. Other than that, simply try to run as follows:
+
+```console
+$ terraform init
+…
+Initializing the backend...
+Initializing modules...
+Initializing provider plugins...
+
+Terraform has been successfully initialized!
+
+You may now begin working with Terraform. Try running "terraform plan" to see
+any changes that are required for your infrastructure. All Terraform commands
+should now work.
+
+If you ever set or change modules or backend configuration for Terraform,
+rerun this command to reinitialize your working directory. If you forget, other
+commands will detect it and remind you to do so if necessary.
+$ terraform plan
+….
+
+Changes to Outputs:
+  + part1 = secret
+  + part2 = also secret
+
+You can apply this plan to save these new output values to the Terraform state, without changing any real infrastructure.
+```
diff --git a/2025/day02/range/main.tf b/2025/day02/range/main.tf
index 7d3f86f..b8a4a06 100644
--- a/2025/day02/range/main.tf
+++ b/2025/day02/range/main.tf
@@ -16,8 +16,8 @@ locals {
   maximum      = substr(tostring(var.max), 0, local.digits)
   real_maximum = length(tostring(var.max)) % var.repetitions == 0 ? tonumber(local.maximum) : pow(10, local.digits)
 
-  min_digits = max(floor(length(tostring(var.min)) / var.repetitions), 1)
-  minimum    = tonumber(substr(tostring(var.min), 0, local.min_digits))
+  minimum_prefix = substr(tostring(var.min), 0, length(tostring(var.min)) - local.digits * (var.repetitions - 1))
+  minimum        = local.minimum_prefix == "" ? 1 : tonumber(local.minimum_prefix)
 
   count = max(local.real_maximum - local.minimum + 1, 1)
 
diff --git a/2025/day02/range2/main.tf b/2025/day02/range2/main.tf
index 722f109..68a4faa 100644
--- a/2025/day02/range2/main.tf
+++ b/2025/day02/range2/main.tf
@@ -12,10 +12,10 @@ locals {
 
 module "range" {
   source      = "../range"
-  count       = local.digits
+  count       = local.digits - 1
   max         = var.max
   min         = var.min
-  repetitions = count.index + 1
+  repetitions = count.index + 2
 }
 
 locals {
diff --git a/2025/day02/tests.tftest.hcl b/2025/day02/tests.tftest.hcl
index d2fee17..f755873 100644
--- a/2025/day02/tests.tftest.hcl
+++ b/2025/day02/tests.tftest.hcl
@@ -1,4 +1,4 @@
-run "sample-1" {
+run "sample-1-1" {
   module {
     source = "./range"
   }
@@ -14,7 +14,7 @@ run "sample-1" {
   }
 }
 
-run "sample-2" {
+run "sample-1-2" {
   module {
     source = "./range"
   }
@@ -29,3 +29,100 @@ run "sample-2" {
     error_message = "Incorrect result"
   }
 }
+
+run "sample-2-1" {
+  module {
+    source = "./range2"
+  }
+
+  variables {
+    min = 11
+    max = 22
+  }
+
+  assert {
+    condition     = output.invalid_sum == 33
+    error_message = "Incorrect result"
+  }
+}
+
+run "sample-2-2" {
+  module {
+    source = "./range2"
+  }
+
+  variables {
+    min = 95
+    max = 115
+  }
+
+  assert {
+    condition     = output.invalid_sum == 210
+    error_message = "Incorrect result"
+  }
+}
+
+run "sample-2-3" {
+  module {
+    source = "./range2"
+  }
+
+  variables {
+    min = 998
+    max = 1012
+  }
+
+  assert {
+    condition     = output.invalid_sum == 2009
+    error_message = "Incorrect result"
+  }
+}
+
+run "sample-2-2-detail" {
+  module {
+    source = "./range"
+  }
+
+  variables {
+    min         = 95
+    max         = 115
+    repetitions = 3
+  }
+
+  assert {
+    condition     = output.invalid_sum == 111
+    error_message = "Incorrect result"
+  }
+}
+
+run "sample-2-10" {
+  module {
+    source = "./range2"
+  }
+
+  variables {
+    min = 824824821
+    max = 824824827
+  }
+
+  assert {
+    condition     = output.invalid_sum == 824824824
+    error_message = "Incorrect result"
+  }
+}
+
+run "sample-2-11" {
+  module {
+    source = "./range2"
+  }
+
+  variables {
+    min = 2121212118
+    max = 2121212124
+  }
+
+  assert {
+    condition     = output.invalid_sum == 2121212121
+    error_message = "Incorrect result"
+  }
+}