[New Exercise]: Space Age

config.json

@@ -261,6 +261,16 @@
         "prerequisites": [],
         "difficulty": 1
       },
+      {
+        "slug": "space-age",
+        "name": "Space Age",
+        "uuid": "76c5078c-9255-44a6-97dd-aab7a1099907",
+        "practices": [
+            "dictionaries"
+        ],
+        "prerequisites": [],
+        "difficulty": 1
+      },
       {
         "slug": "etl",
         "name": "Etl",

exercises/practice/space-age/.docs/instructions.md

@@ -0,0 +1,25 @@
+# Instructions
+
+Given an age in seconds, calculate how old someone would be on:
+
+- Mercury: orbital period 0.2408467 Earth years
+- Venus: orbital period 0.61519726 Earth years
+- Earth: orbital period 1.0 Earth years, 365.25 Earth days, or 31557600 seconds
+- Mars: orbital period 1.8808158 Earth years
+- Jupiter: orbital period 11.862615 Earth years
+- Saturn: orbital period 29.447498 Earth years
+- Uranus: orbital period 84.016846 Earth years
+- Neptune: orbital period 164.79132 Earth years
+
+So if you were told someone were 1,000,000,000 seconds old, you should
+be able to say that they're 31.69 Earth-years old.
+
+If you're wondering why Pluto didn't make the cut, go watch [this YouTube video][pluto-video].
+
+Note: The actual length of one complete orbit of the Earth around the sun is closer to 365.256 days (1 sidereal year).
+The Gregorian calendar has, on average, 365.2425 days.
+While not entirely accurate, 365.25 is the value used in this exercise.
+See [Year on Wikipedia][year] for more ways to measure a year.
+
+[pluto-video]: https://www.youtube.com/watch?v=Z_2gbGXzFbs
+[year]: https://en.wikipedia.org/wiki/Year#Summary

exercises/practice/space-age/.meta/SpaceAge.example.ps1

@@ -0,0 +1,40 @@
+Function Get-SpaceAge() {
+    <#
+    .SYNOPSIS
+    Given an age in seconds, calculate how old someone would be on a planet in the solar system. (RIP Pluto)
+
+    .DESCRIPTION
+    The function takes a positive integer, and return a double (float) to show how old someone is on a specific planet.
+
+    .PARAMETER $Seconds
+    The seconds of a person's age.
+
+    .PARAMETER $Planet
+    The planet to calculate how old the person would be on it.
+    Note: Since the planets in the solar system is a known shortlist, we can just validate the input with a set of values in the params.
+    If no planet is specified, it should be default to Earth.
+
+    .EXAMPLE
+    Get-SpaceAge -Seconds 1000000000 -Planet Neptune
+    Retuns: 0.19
+    #>
+    [CmdletBinding()]
+    Param(
+        [int]$Seconds,
+        [ValidateSet("Earth", "Mercury","Venus", "Mars", "Jupiter", "Saturn", "Uranus", "Neptune", ErrorMessage = "Invalid planet")]
+        [string]$Planet = "Earth"
+    )
+
+    $OrbitalPeriods = @{
+        'Mercury'   = 0.2408467
+        'Venus'     = 0.61519726
+        'Earth'     = 1
+        'Mars'      = 1.8808158
+        'Jupiter'   = 11.862615
+        'Saturn'    = 29.447498
+        'Uranus'    = 84.016846
+        'Neptune'   = 164.79132
+    }
+    $EarthAge = $Seconds / 31557600
+    return [math]::Round($EarthAge / $OrbitalPeriods[$Planet],2)
+}

exercises/practice/space-age/.meta/config.json

@@ -0,0 +1,17 @@
+{
+  "authors": ["glaxxie"],
+  "files": {
+    "solution": [
+      "SpaceAge.ps1"
+    ],
+    "test": [
+      "SpaceAge.tests.ps1"
+    ],
+    "example": [
+      ".meta/SpaceAge.example.ps1"
+    ]
+  },
+  "blurb": "Given an age in seconds, calculate how old someone is in terms of a given planet's solar years.",
+  "source": "Partially inspired by Chapter 1 in Chris Pine's online Learn to Program tutorial.",
+  "source_url": "https://pine.fm/LearnToProgram/?Chapter=01"
+}

exercises/practice/space-age/.meta/tests.toml

@@ -0,0 +1,37 @@
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
+
+[84f609af-5a91-4d68-90a3-9e32d8a5cd34]
+description = "age on Earth"
+
+[ca20c4e9-6054-458c-9312-79679ffab40b]
+description = "age on Mercury"
+
+[502c6529-fd1b-41d3-8fab-65e03082b024]
+description = "age on Venus"
+
+[9ceadf5e-a0d5-4388-9d40-2c459227ceb8]
+description = "age on Mars"
+
+[42927dc3-fe5e-4f76-a5b5-f737fc19bcde]
+description = "age on Jupiter"
+
+[8469b332-7837-4ada-b27c-00ee043ebcad]
+description = "age on Saturn"
+
+[999354c1-76f8-4bb5-a672-f317b6436743]
+description = "age on Uranus"
+
+[80096d30-a0d4-4449-903e-a381178355d8]
+description = "age on Neptune"
+
+[57b96e2a-1178-40b7-b34d-f3c9c34e4bf4]
+description = "invalid planet causes error"

exercises/practice/space-age/SpaceAge.ps1

@@ -0,0 +1,28 @@
+Function Get-SpaceAge() {
+    <#
+    .SYNOPSIS
+    Given an age in seconds, calculate how old someone would be on a planet in the solar system. (RIP Pluto)
+
+    .DESCRIPTION
+    The function takes a positive integer, and return a double (float) to show how old someone is on a specific planet.
+
+    .PARAMETER $Seconds
+    The seconds of a person's age.
+
+    .PARAMETER $Planet
+    The planet to calculate how old the person would be on it.
+    Note: Since the planets in the solar system is a known shortlist, we can just validate the input with a set of values in the params.
+    If no planet is specified, it should be default to Earth.
+
+    .EXAMPLE
+    Get-SpaceAge -Seconds 1000000000 -Planet Neptune
+    Retuns: 0.19
+    #>
+    [CmdletBinding()]
+    Param(
+        [int]$Seconds,
+        [ValidateSet]
+        [string]$Planet
+    )
+    Throw "Please implement this function"
+}

exercises/practice/space-age/SpaceAge.tests.ps1

@@ -0,0 +1,76 @@
+BeforeAll {
+    . "./SpaceAge.ps1"
+}
+
+Describe "Space Age test cases" {
+    Context "passing tests" {
+        It "age on Earth" {
+            $got  = Get-SpaceAge -Seconds 1000000000 -Planet Earth
+            $want = 31.69
+
+            $got | Should -Be $want
+        }
+
+        It "no planet provided should default to Earth" {
+            $got  = Get-SpaceAge -Seconds 1000000000
+            $want = 31.69
+
+            $got | Should -Be $want
+        }
+
+        It "age on Mercury" {
+            $got  = Get-SpaceAge -Seconds 2134835688 -Planet Mercury
+            $want = 280.88
+
+            $got | Should -Be $want
+        }
+
+        It "age on Venus" {
+            $got  = Get-SpaceAge -Seconds 189839836 -Planet Venus
+            $want = 9.78
+
+            $got | Should -Be $want
+        }
+
+        It "age on Mars" {
+            $got  = Get-SpaceAge -Seconds 2129871239 -Planet Mars
+            $want = 35.88
+
+            $got | Should -Be $want
+        }
+
+        It "age on Jupiter" {
+            $got  = Get-SpaceAge -Seconds 901876382 -Planet Jupiter
+            $want = 2.41
+
+            $got | Should -Be $want
+        }
+
+        It "age on Saturn" {
+            $got  = Get-SpaceAge -Seconds 2000000000 -Planet Saturn
+            $want = 2.15
+
+            $got | Should -Be $want
+        }
+
+        It "age on Uranus" {
+            $got  = Get-SpaceAge -Seconds 1210123456 -Planet Uranus
+            $want = 0.46
+
+            $got | Should -Be $want
+        }
+
+        It "age on Neptune" {
+            $got  = Get-SpaceAge -Seconds 1821023456 -Planet Neptune
+            $want = 0.35
+
+            $got | Should -Be $want
+        }
+    }
+
+    Context "invalid input" {
+        It "invalid planet give error" {
+            { Get-SpaceAge -Seconds 1000000000 -Planet Pluto } | Should -Throw "Cannot validate argument on parameter 'Planet'. Invalid planet"
+        }
+    }
+}