stdlib: Implement common assert commands (#8515)

Implement common assert commands with tests.
Fixes #8419.

---------

Co-authored-by: Mate Farkas <Mate.Farkas@oneidentity.com>

crates/nu-utils/standard_library/std.nu

@@ -1,18 +1,11 @@
 # std.nu, `used` to load all standard library components
 
-# ---------------- builtin std functions --------------------
+# Universal assert command
-
+#
-def _assertion-error [start, end, label, message?: string] {
+# If the condition is not true, it generates an error.
-    error make {
+#
-        msg: ($message | default "Assertion failed."),
+# # Example
-        label: {
+#
-            text: $label,
-            start: $start,
-            end: $end
-        }
-    }
-}
-
 # ```nushell
 # >_ assert (3 == 3)
 # >_ assert (42 == 3)
@@ -26,51 +19,183 @@ def _assertion-error [start, end, label, message?: string] {
 #  13 │
 #     ╰────
 # ```
-export def assert [cond: bool, message?: string] {
-    if $cond { return }
-    let span = (metadata $cond).span
-    _assertion-error $span.start $span.end "It is not true." $message
-}
-
-# ```nushell
-# ❯ assert eq 3 3
-# ❯ assert eq 3 1
-# Error:
-#   × Assertion failed.
-#    ╭─[entry #14:1:1]
-#  1 │ assert eq 3 1
-#    ·           ─┬─
-#    ·            ╰── They are not equal: 3 != 1
-#    ╰────
-#
 #
+# The --error-label flag can be used if you want to create a custom assert command:
 # ```
-export def "assert eq" [left: any, right: any, message?: string] {
+# def "assert even" [number: int] {
-    let left_start = (metadata $left).span.start
+#     assert ($number mod 2 == 0) --error-label {
-    let right_end = (metadata $right).span.end
+#         start: (metadata $number).span.start,
-
+#         end: (metadata $number).span.end,
-    if ($left != $right) {
+#         text: $"($number) is not an even number",
-        _assertion-error $left_start $right_end $"They are not equal: ($left) != ($right)" $message
+#     }
+# }
+# ```
+export def assert [
+    condition: bool, # Condition, which should be true 
+    message?: string, # Optional error message
+    --error-label: record # Label for `error make` if you want to create a custom assert
+] {
+    if $condition { return }
+    let span = (metadata $condition).span
+    error make {
+        msg: ($message | default "Assertion failed."),
+        label: ($error_label | default {
+            text: "It is not true.",
+            start: (metadata $condition).span.start,
+            end: (metadata $condition).span.end
+        })
     }
 }
 
-# ```nushell
+# Assert that executing the code generates an error
-# ❯ assert ne 1 3
+#
-# ❯ assert ne 42 42
+# For more documentation see the assert command
-# Error:
+# 
-#   × Assertion failed.
+# # Examples
-#    ╭─[entry #23:1:1]
+#
-#  1 │ assert ne 42 42
+# > assert error {|| missing_command} # passes
-#    ·           ──┬──
+# > assert error {|| 12} # fails
-#    ·             ╰── They both are 42
+export def "assert error" [
-#    ╰────
+    code: closure,
-# ```
+    message?: string
-export def "assert ne" [left: any, right: any, message?: string] {
+] {
-    let left_start = (metadata $left).span.start
+    let error_raised = (try { do $code; false } catch { true })
-    let right_end = (metadata $right).span.end
+    assert ($error_raised) $message --error-label {
+        start: (metadata $code).span.start
+        end: (metadata $code).span.end
+        text: $"There were no error during code execution: (view source $code)"
+    }
+}
 
-    if ($left == $right) {
+# Assert $left == $right
-        _assertion-error $left_start $right_end $"They both are ($left)" $message
+#
+# For more documentation see the assert command
+#
+# # Examples
+# 
+# > assert equal 1 1 # passes
+# > assert equal (0.1 + 0.2) 0.3
+# > assert equal 1 2 # fails
+export def "assert equal" [left: any, right: any, message?: string] {
+    assert ($left == $right) $message --error-label {
+        start: (metadata $left).span.start
+        end: (metadata $right).span.end
+        text: $"They are not equal. Left = ($left). Right = ($right)."
+    }
+}
+
+# Assert $left != $right
+#
+# For more documentation see the assert command
+#
+# # Examples
+#
+# > assert not equal 1 2 # passes
+# > assert not equal 1 "apple" # passes
+# > assert not equal 7 7 # fails
+export def "assert not equal" [left: any, right: any, message?: string] {
+    assert ($left != $right) $message --error-label {
+        start: (metadata $left).span.start
+        end: (metadata $right).span.end
+        text: $"They both are ($left)."
+    }
+}
+
+# Assert $left <= $right
+#
+# For more documentation see the assert command
+#
+# # Examples
+#
+# > assert less or equal 1 2 # passes
+# > assert less or equal 1 1 # passes
+# > assert less or equal 1 0 # fails
+export def "assert less or equal" [left: any, right: any, message?: string] {
+    assert ($left <= $right) $message --error-label {
+        start: (metadata $left).span.start
+        end: (metadata $right).span.end
+        text: $"Left: ($left), Right: ($right)"
+    }
+}
+
+# Assert $left < $right
+#
+# For more documentation see the assert command
+#
+# # Examples
+#
+# > assert less 1 2 # passes
+# > assert less 1 1 # fails
+export def "assert less" [left: any, right: any, message?: string] {
+    assert ($left < $right) $message --error-label {
+        start: (metadata $left).span.start
+        end: (metadata $right).span.end
+        text: $"Left: ($left), Right: ($right)"
+    }
+}
+
+# Assert $left > $right
+#
+# For more documentation see the assert command
+#
+# # Examples
+#
+# > assert greater 2 1 # passes
+# > assert greater 2 2 # fails
+export def "assert greater" [left: any, right: any, message?: string] {
+    assert ($left > $right) $message --error-label {
+        start: (metadata $left).span.start
+        end: (metadata $right).span.end
+        text: $"Left: ($left), Right: ($right)"
+    }
+}
+
+# Assert $left >= $right
+#
+# For more documentation see the assert command
+#
+# # Examples
+#
+# > assert greater or equal 2 1 # passes
+# > assert greater or equal 2 2 # passes
+# > assert greater or equal 1 2 # fails
+export def "assert greater or equal" [left: any, right: any, message?: string] {
+    assert ($left >= $right) $message --error-label {
+        start: (metadata $left).span.start
+        end: (metadata $right).span.end
+        text: $"Left: ($left), Right: ($right)"
+    }
+}
+
+# Assert length of $left is $right
+#
+# For more documentation see the assert command
+#
+# # Examples
+#
+# > assert length [0, 0] 2 # passes
+# > assert length [0] 3 # fails
+export def "assert length" [left: list, right: int, message?: string] {
+    assert (($left | length) == $right) $message --error-label {
+        start: (metadata $left).span.start
+        end: (metadata $right).span.end
+        text: $"Length of ($left) is ($left | length), not ($right)"
+    }
+}
+
+# Assert that ($left | str contains $right)
+#
+# For more documentation see the assert command
+#
+# # Examples
+#
+# > assert str contains "arst" "rs" # passes
+# > assert str contains "arst" "k" # fails
+export def "assert str contains" [left: string, right: string, message?: string] {
+    assert ($left | str contains $right) $message --error-label {
+        start: (metadata $left).span.start
+        end: (metadata $right).span.end
+        text: $"'($left)' does not contain '($right)'."
     }
 }
 
@@ -125,7 +250,7 @@ export def match [
 #     std path add "bar" "baz"
 #     std path add "fooo" --append
 #
-#     assert eq $env.PATH ["bar" "baz" "foo" "fooo"]
+#     assert equal $env.PATH ["bar" "baz" "foo" "fooo"]
 #
 #     print (std path add "returned" --ret)
 # }

crates/nu-utils/standard_library/test_asserts.nu

@@ -0,0 +1,64 @@
+use std.nu *
+
+export def test_assert [] {
+    assert true
+    assert (1 + 2 == 3)
+    assert error { assert false }
+    assert error { assert (1 + 2 == 4) }
+}
+
+export def test_assert_equal [] {
+    assert equal (1 + 2) 3
+    assert equal (0.1 + 0.2 | into string | into decimal) 0.3 # 0.30000000000000004 == 0.3
+    assert error { assert equal 1 "foo" }
+    assert error { assert equal (1 + 2) 4) }
+}
+
+export def test_assert_not_equal [] {
+    assert not equal (1 + 2) 4
+    assert not equal 1 "foo"
+    assert not equal (1 + 2) 3)
+    assert error { assert not equal 1 1 }
+}
+
+export def test_assert_error [] {
+    let failing_code = {|| missing_code_to_run}
+    assert error $failing_code
+
+    let good_code = {|| }
+    let assert_error_raised = (try { do assert $good_code; false } catch { true })
+    assert $assert_error_raised "The assert error should raise an error if there is no error in the executed code."
+}
+
+export def test_assert_less [] {
+    assert less 1 2
+    assert error { assert less 1 1 }
+}
+
+export def test_assert_less_or_equal [] {
+    assert less or equal 1 2
+    assert less or equal 1 1
+    assert error { assert less or equal 1 0 }
+}
+
+export def test_assert_greater [] {
+    assert greater 2 1
+    assert error { assert greater 2 2 }
+}
+
+export def test_assert_greater_or_equal [] {
+    assert greater or equal 1 1
+    assert greater or equal 2 1
+    assert error { assert greater or equal 0 1 }
+}
+
+export def test_assert_length [] {
+    assert length [0, 0, 0]  3
+    assert error { assert length [0, 0] 3 }
+}
+
+# export def test_assert_§ [] {
+#     assert §
+#     assert error { assert § }
+# }
+

crates/nu-utils/standard_library/test_dirs.nu

@@ -1,4 +1,5 @@
-use std.nu assert
+use std.nu "assert length"
+use std.nu "assert equal"
 
 def clean [path: path] {
     cd $path
@@ -21,31 +22,31 @@ export def test_dirs_command [] {
         use std.nu "dirs drop"
         use std.nu "dirs show"
 
-        assert (1 == ($env.DIRS_LIST | length)) "list is just pwd after initialization"
+        assert length $env.DIRS_LIST 1 "list is just pwd after initialization"
-        assert ($base_path == $env.DIRS_LIST.0) "list is just pwd after initialization"
+        assert equal $base_path $env.DIRS_LIST.0 "list is just pwd after initialization"
 
         dirs next
-        assert ($base_path == $env.DIRS_LIST.0) "next wraps at end of list"
+        assert equal $base_path $env.DIRS_LIST.0 "next wraps at end of list"
 
         dirs prev
-        assert ($base_path == $env.DIRS_LIST.0) "prev wraps at top of list"
+        assert equal $base_path $env.DIRS_LIST.0 "prev wraps at top of list"
 
         dirs add $path_b $path_a
-        assert ($path_b == $env.PWD) "add changes PWD to first added dir"
+        assert equal $path_b $env.PWD "add changes PWD to first added dir"
-        assert (3 == ($env.DIRS_LIST | length)) "add in fact adds to list"
+        assert length $env.DIRS_LIST 3 "add in fact adds to list"
-        assert ($path_a == $env.DIRS_LIST.2) "add in fact adds to list"
+        assert equal $path_a $env.DIRS_LIST.2 "add in fact adds to list"
 
         dirs next 2
-        assert ($base_path == $env.PWD) "next wraps at end of list"
+        assert equal $base_path $env.PWD "next wraps at end of list"
 
         dirs prev 1
-        assert ($path_a == $env.PWD) "prev wraps at start of list"
+        assert equal $path_a $env.PWD "prev wraps at start of list"
 
         dirs drop
-        assert (2 == ($env.DIRS_LIST | length)) "drop removes from list"
+        assert length $env.DIRS_LIST 2 "drop removes from list"
-        assert ($base_path == $env.PWD) "drop changes PWD to next in list (after dropped element)"
+        assert equal $base_path $env.PWD "drop changes PWD to next in list (after dropped element)"
 
-        assert ((dirs show) == [[active path]; [true $base_path] [false $path_b]]) "show table contains expected information"
+        assert equal (dirs show) [[active path]; [true $base_path] [false $path_b]] "show table contains expected information"
     } catch { |error|
         clean $base_path
 

crates/nu-utils/standard_library/test_logger.nu

@@ -8,13 +8,13 @@ def run [system_level, message_level] {
 }
 def "assert no message" [system_level, message_level] {
     let output = (run $system_level $message_level)
-    assert eq $output ""
+    assert equal "" $output
 }
 
 def "assert message" [system_level, message_level, message_level_str] {
     let output = (run $system_level $message_level)
-    assert ($output | str contains $message_level_str)
+    assert str contains $output $message_level_str
-    assert ($output | str contains "test message")
+    assert str contains $output "test message"
 }
 
 export def test_critical [] {

crates/nu-utils/standard_library/test_std.nu

@@ -1,28 +1,5 @@
 use std.nu
 
-export def test_assert [] {
-    def test_failing [code: closure] {
-        let code_did_run = (try { do $code; true } catch { false })
-
-        if $code_did_run {
-            error make {msg: (view source $code)}
-        }
-    }
-
-    std assert true
-    std assert (1 + 2 == 3)
-    test_failing { std assert false }
-    test_failing { std assert (1 + 2 == 4) }
-
-    std assert eq (1 + 2) 3
-    test_failing { std assert eq 1 "foo" }
-    test_failing { std assert eq (1 + 2) 4) }
-
-    std assert ne (1 + 2) 4
-    std assert ne 1 "foo"
-    std assert ne (1 + 2) 3)
-}
-
 export def test_match [] {
     use std.nu assert
 
@@ -41,24 +18,24 @@ export def test_match [] {
 }
 
 export def test_path_add [] {
-    use std.nu "assert eq"
+    use std.nu "assert equal"
 
     with-env [PATH []] {
-        assert eq $env.PATH []
+        assert equal $env.PATH []
 
         std path add "/foo/"
-        assert eq $env.PATH ["/foo/"]
+        assert equal $env.PATH ["/foo/"]
 
         std path add "/bar/" "/baz/"
-        assert eq $env.PATH ["/bar/", "/baz/", "/foo/"]
+        assert equal $env.PATH ["/bar/", "/baz/", "/foo/"]
 
         let-env PATH = []
 
         std path add "foo"
         std path add "bar" "baz" --append
-        assert eq $env.PATH ["foo", "bar", "baz"]
+        assert equal $env.PATH ["foo", "bar", "baz"]
 
-        assert eq (std path add "fooooo" --ret) ["fooooo", "foo", "bar", "baz"]
+        assert equal (std path add "fooooo" --ret) ["fooooo", "foo", "bar", "baz"]
-        assert eq $env.PATH ["fooooo", "foo", "bar", "baz"]
+        assert equal $env.PATH ["fooooo", "foo", "bar", "baz"]
     }
 }