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diff --git a/tinyusb/test/vendor/ceedling/docs/UnityAssertionsReference.md b/tinyusb/test/vendor/ceedling/docs/UnityAssertionsReference.md deleted file mode 100755 index eb855f3c..00000000 --- a/tinyusb/test/vendor/ceedling/docs/UnityAssertionsReference.md +++ /dev/null @@ -1,779 +0,0 @@ -# Unity Assertions Reference - -## Background and Overview - -### Super Condensed Version - -- An assertion establishes truth (i.e. boolean True) for a single condition. -Upon boolean False, an assertion stops execution and reports the failure. -- Unity is mainly a rich collection of assertions and the support to gather up -and easily execute those assertions. -- The structure of Unity allows you to easily separate test assertions from -source code in, well, test code. -- Unity's assertions: -- Come in many, many flavors to handle different C types and assertion cases. -- Use context to provide detailed and helpful failure messages. -- Document types, expected values, and basic behavior in your source code for -free. - - -### Unity Is Several Things But Mainly It's Assertions - -One way to think of Unity is simply as a rich collection of assertions you can -use to establish whether your source code behaves the way you think it does. -Unity provides a framework to easily organize and execute those assertions in -test code separate from your source code. - - -### What's an Assertion? - -At their core, assertions are an establishment of truth - boolean truth. Was this -thing equal to that thing? Does that code doohickey have such-and-such property -or not? You get the idea. Assertions are executable code (to appreciate the big -picture on this read up on the difference between -[link:Dynamic Verification and Static Analysis]). A failing assertion stops -execution and reports an error through some appropriate I/O channel (e.g. -stdout, GUI, file, blinky light). - -Fundamentally, for dynamic verification all you need is a single assertion -mechanism. In fact, that's what the [assert() macro in C's standard library](http://en.wikipedia.org/en/wiki/Assert.h) -is for. So why not just use it? Well, we can do far better in the reporting -department. C's `assert()` is pretty dumb as-is and is particularly poor for -handling common data types like arrays, structs, etc. And, without some other -support, it's far too tempting to litter source code with C's `assert()`'s. It's -generally much cleaner, manageable, and more useful to separate test and source -code in the way Unity facilitates. - - -### Unity's Assertions: Helpful Messages _and_ Free Source Code Documentation - -Asserting a simple truth condition is valuable, but using the context of the -assertion is even more valuable. For instance, if you know you're comparing bit -flags and not just integers, then why not use that context to give explicit, -readable, bit-level feedback when an assertion fails? - -That's what Unity's collection of assertions do - capture context to give you -helpful, meaningful assertion failure messages. In fact, the assertions -themselves also serve as executable documentation about types and values in your -source code. So long as your tests remain current with your source and all those -tests pass, you have a detailed, up-to-date view of the intent and mechanisms in -your source code. And due to a wondrous mystery, well-tested code usually tends -to be well designed code. - - -## Assertion Conventions and Configurations - -### Naming and Parameter Conventions - -The convention of assertion parameters generally follows this order: - - TEST_ASSERT_X( {modifiers}, {expected}, actual, {size/count} ) - -The very simplest assertion possible uses only a single "actual" parameter (e.g. -a simple null check). - -"Actual" is the value being tested and unlike the other parameters in an -assertion construction is the only parameter present in all assertion variants. -"Modifiers" are masks, ranges, bit flag specifiers, floating point deltas. -"Expected" is your expected value (duh) to compare to an "actual" value; it's -marked as an optional parameter because some assertions only need a single -"actual" parameter (e.g. null check). -"Size/count" refers to string lengths, number of array elements, etc. - -Many of Unity's assertions are clear duplications in that the same data type -is handled by several assertions. The differences among these are in how failure -messages are presented. For instance, a `_HEX` variant of an assertion prints -the expected and actual values of that assertion formatted as hexadecimal. - - -#### TEST_ASSERT_X_MESSAGE Variants - -_All_ assertions are complemented with a variant that includes a simple string -message as a final parameter. The string you specify is appended to an assertion -failure message in Unity output. - -For brevity, the assertion variants with a message parameter are not listed -below. Just tack on `_MESSAGE` as the final component to any assertion name in -the reference list below and add a string as the final parameter. - -_Example:_ - - TEST_ASSERT_X( {modifiers}, {expected}, actual, {size/count} ) - -becomes messageified like thus... - - TEST_ASSERT_X_MESSAGE( {modifiers}, {expected}, actual, {size/count}, message ) - -Notes: -- The `_MESSAGE` variants intentionally do not support `printf` style formatting - since many embedded projects don't support or avoid `printf` for various reasons. - It is possible to use `sprintf` before the assertion to assemble a complex fail - message, if necessary. -- If you want to output a counter value within an assertion fail message (e.g. from - a loop) , building up an array of results and then using one of the `_ARRAY` - assertions (see below) might be a handy alternative to `sprintf`. - - -#### TEST_ASSERT_X_ARRAY Variants - -Unity provides a collection of assertions for arrays containing a variety of -types. These are documented in the Array section below. These are almost on par -with the `_MESSAGE`variants of Unity's Asserts in that for pretty much any Unity -type assertion you can tack on `_ARRAY` and run assertions on an entire block of -memory. - - TEST_ASSERT_EQUAL_TYPEX_ARRAY( expected, actual, {size/count} ) - -"Expected" is an array itself. -"Size/count" is one or two parameters necessary to establish the number of array -elements and perhaps the length of elements within the array. - -Notes: -- The `_MESSAGE` variant convention still applies here to array assertions. The -`_MESSAGE` variants of the `_ARRAY` assertions have names ending with -`_ARRAY_MESSAGE`. -- Assertions for handling arrays of floating point values are grouped with float -and double assertions (see immediately following section). - - -### TEST_ASSERT_EACH_EQUAL_X Variants - -Unity provides a collection of assertions for arrays containing a variety of -types which can be compared to a single value as well. These are documented in -the Each Equal section below. these are almost on par with the `_MESSAGE` -variants of Unity's Asserts in that for pretty much any Unity type assertion you -can inject _EACH_EQUAL and run assertions on an entire block of memory. - - TEST_ASSERT_EACH_EQUAL_TYPEX( expected, actual, {size/count} ) - -"Expected" is a single value to compare to. -"Actual" is an array where each element will be compared to the expected value. -"Size/count" is one of two parameters necessary to establish the number of array -elements and perhaps the length of elements within the array. - -Notes: -- The `_MESSAGE` variant convention still applies here to Each Equal assertions. -- Assertions for handling Each Equal of floating point values are grouped with -float and double assertions (see immediately following section). - - -### Configuration - -#### Floating Point Support Is Optional - -Support for floating point types is configurable. That is, by defining the -appropriate preprocessor symbols, floats and doubles can be individually enabled -or disabled in Unity code. This is useful for embedded targets with no floating -point math support (i.e. Unity compiles free of errors for fixed point only -platforms). See Unity documentation for specifics. - - -#### Maximum Data Type Width Is Configurable - -Not all targets support 64 bit wide types or even 32 bit wide types. Define the -appropriate preprocessor symbols and Unity will omit all operations from -compilation that exceed the maximum width of your target. See Unity -documentation for specifics. - - -## The Assertions in All Their Blessed Glory - -### Basic Fail and Ignore - -##### `TEST_FAIL()` - -This fella is most often used in special conditions where your test code is -performing logic beyond a simple assertion. That is, in practice, `TEST_FAIL()` -will always be found inside a conditional code block. - -_Examples:_ -- Executing a state machine multiple times that increments a counter your test -code then verifies as a final step. -- Triggering an exception and verifying it (as in Try / Catch / Throw - see the -[CException](https://github.com/ThrowTheSwitch/CException) project). - -##### `TEST_IGNORE()` - -Marks a test case (i.e. function meant to contain test assertions) as ignored. -Usually this is employed as a breadcrumb to come back and implement a test case. -An ignored test case has effects if other assertions are in the enclosing test -case (see Unity documentation for more). - -### Boolean - -##### `TEST_ASSERT (condition)` - -##### `TEST_ASSERT_TRUE (condition)` - -##### `TEST_ASSERT_FALSE (condition)` - -##### `TEST_ASSERT_UNLESS (condition)` - -A simple wording variation on `TEST_ASSERT_FALSE`.The semantics of -`TEST_ASSERT_UNLESS` aid readability in certain test constructions or -conditional statements. - -##### `TEST_ASSERT_NULL (pointer)` - -##### `TEST_ASSERT_NOT_NULL (pointer)` - - -### Signed and Unsigned Integers (of all sizes) - -Large integer sizes can be disabled for build targets that do not support them. -For example, if your target only supports up to 16 bit types, by defining the -appropriate symbols Unity can be configured to omit 32 and 64 bit operations -that would break compilation (see Unity documentation for more). Refer to -Advanced Asserting later in this document for advice on dealing with other word -sizes. - -##### `TEST_ASSERT_EQUAL_INT (expected, actual)` - -##### `TEST_ASSERT_EQUAL_INT8 (expected, actual)` - -##### `TEST_ASSERT_EQUAL_INT16 (expected, actual)` - -##### `TEST_ASSERT_EQUAL_INT32 (expected, actual)` - -##### `TEST_ASSERT_EQUAL_INT64 (expected, actual)` - -##### `TEST_ASSERT_EQUAL (expected, actual)` - -##### `TEST_ASSERT_NOT_EQUAL (expected, actual)` - -##### `TEST_ASSERT_EQUAL_UINT (expected, actual)` - -##### `TEST_ASSERT_EQUAL_UINT8 (expected, actual)` - -##### `TEST_ASSERT_EQUAL_UINT16 (expected, actual)` - -##### `TEST_ASSERT_EQUAL_UINT32 (expected, actual)` - -##### `TEST_ASSERT_EQUAL_UINT64 (expected, actual)` - - -### Unsigned Integers (of all sizes) in Hexadecimal - -All `_HEX` assertions are identical in function to unsigned integer assertions -but produce failure messages with the `expected` and `actual` values formatted -in hexadecimal. Unity output is big endian. - -##### `TEST_ASSERT_EQUAL_HEX (expected, actual)` - -##### `TEST_ASSERT_EQUAL_HEX8 (expected, actual)` - -##### `TEST_ASSERT_EQUAL_HEX16 (expected, actual)` - -##### `TEST_ASSERT_EQUAL_HEX32 (expected, actual)` - -##### `TEST_ASSERT_EQUAL_HEX64 (expected, actual)` - - -### Masked and Bit-level Assertions - -Masked and bit-level assertions produce output formatted in hexadecimal. Unity -output is big endian. - - -##### `TEST_ASSERT_BITS (mask, expected, actual)` - -Only compares the masked (i.e. high) bits of `expected` and `actual` parameters. - - -##### `TEST_ASSERT_BITS_HIGH (mask, actual)` - -Asserts the masked bits of the `actual` parameter are high. - - -##### `TEST_ASSERT_BITS_LOW (mask, actual)` - -Asserts the masked bits of the `actual` parameter are low. - - -##### `TEST_ASSERT_BIT_HIGH (bit, actual)` - -Asserts the specified bit of the `actual` parameter is high. - - -##### `TEST_ASSERT_BIT_LOW (bit, actual)` - -Asserts the specified bit of the `actual` parameter is low. - -### Integer Less Than / Greater Than - -These assertions verify that the `actual` parameter is less than or greater -than `threshold` (exclusive). For example, if the threshold value is 0 for the -greater than assertion will fail if it is 0 or less. - -##### `TEST_ASSERT_GREATER_THAN (threshold, actual)` - -##### `TEST_ASSERT_GREATER_THAN_INT (threshold, actual)` - -##### `TEST_ASSERT_GREATER_THAN_INT8 (threshold, actual)` - -##### `TEST_ASSERT_GREATER_THAN_INT16 (threshold, actual)` - -##### `TEST_ASSERT_GREATER_THAN_INT32 (threshold, actual)` - -##### `TEST_ASSERT_GREATER_THAN_UINT (threshold, actual)` - -##### `TEST_ASSERT_GREATER_THAN_UINT8 (threshold, actual)` - -##### `TEST_ASSERT_GREATER_THAN_UINT16 (threshold, actual)` - -##### `TEST_ASSERT_GREATER_THAN_UINT32 (threshold, actual)` - -##### `TEST_ASSERT_GREATER_THAN_HEX8 (threshold, actual)` - -##### `TEST_ASSERT_GREATER_THAN_HEX16 (threshold, actual)` - -##### `TEST_ASSERT_GREATER_THAN_HEX32 (threshold, actual)` - -##### `TEST_ASSERT_LESS_THAN (threshold, actual)` - -##### `TEST_ASSERT_LESS_THAN_INT (threshold, actual)` - -##### `TEST_ASSERT_LESS_THAN_INT8 (threshold, actual)` - -##### `TEST_ASSERT_LESS_THAN_INT16 (threshold, actual)` - -##### `TEST_ASSERT_LESS_THAN_INT32 (threshold, actual)` - -##### `TEST_ASSERT_LESS_THAN_UINT (threshold, actual)` - -##### `TEST_ASSERT_LESS_THAN_UINT8 (threshold, actual)` - -##### `TEST_ASSERT_LESS_THAN_UINT16 (threshold, actual)` - -##### `TEST_ASSERT_LESS_THAN_UINT32 (threshold, actual)` - -##### `TEST_ASSERT_LESS_THAN_HEX8 (threshold, actual)` - -##### `TEST_ASSERT_LESS_THAN_HEX16 (threshold, actual)` - -##### `TEST_ASSERT_LESS_THAN_HEX32 (threshold, actual)` - - -### Integer Ranges (of all sizes) - -These assertions verify that the `expected` parameter is within +/- `delta` -(inclusive) of the `actual` parameter. For example, if the expected value is 10 -and the delta is 3 then the assertion will fail for any value outside the range -of 7 - 13. - -##### `TEST_ASSERT_INT_WITHIN (delta, expected, actual)` - -##### `TEST_ASSERT_INT8_WITHIN (delta, expected, actual)` - -##### `TEST_ASSERT_INT16_WITHIN (delta, expected, actual)` - -##### `TEST_ASSERT_INT32_WITHIN (delta, expected, actual)` - -##### `TEST_ASSERT_INT64_WITHIN (delta, expected, actual)` - -##### `TEST_ASSERT_UINT_WITHIN (delta, expected, actual)` - -##### `TEST_ASSERT_UINT8_WITHIN (delta, expected, actual)` - -##### `TEST_ASSERT_UINT16_WITHIN (delta, expected, actual)` - -##### `TEST_ASSERT_UINT32_WITHIN (delta, expected, actual)` - -##### `TEST_ASSERT_UINT64_WITHIN (delta, expected, actual)` - -##### `TEST_ASSERT_HEX_WITHIN (delta, expected, actual)` - -##### `TEST_ASSERT_HEX8_WITHIN (delta, expected, actual)` - -##### `TEST_ASSERT_HEX16_WITHIN (delta, expected, actual)` - -##### `TEST_ASSERT_HEX32_WITHIN (delta, expected, actual)` - -##### `TEST_ASSERT_HEX64_WITHIN (delta, expected, actual)` - - -### Structs and Strings - -##### `TEST_ASSERT_EQUAL_PTR (expected, actual)` - -Asserts that the pointers point to the same memory location. - - -##### `TEST_ASSERT_EQUAL_STRING (expected, actual)` - -Asserts that the null terminated (`'\0'`)strings are identical. If strings are -of different lengths or any portion of the strings before their terminators -differ, the assertion fails. Two NULL strings (i.e. zero length) are considered -equivalent. - - -##### `TEST_ASSERT_EQUAL_MEMORY (expected, actual, len)` - -Asserts that the contents of the memory specified by the `expected` and `actual` -pointers is identical. The size of the memory blocks in bytes is specified by -the `len` parameter. - - -### Arrays - -`expected` and `actual` parameters are both arrays. `num_elements` specifies the -number of elements in the arrays to compare. - -`_HEX` assertions produce failure messages with expected and actual array -contents formatted in hexadecimal. - -For array of strings comparison behavior, see comments for -`TEST_ASSERT_EQUAL_STRING` in the preceding section. - -Assertions fail upon the first element in the compared arrays found not to -match. Failure messages specify the array index of the failed comparison. - -##### `TEST_ASSERT_EQUAL_INT_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_INT8_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_INT16_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_INT32_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_INT64_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_UINT_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_UINT8_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_UINT16_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_UINT32_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_UINT64_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_HEX_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_HEX8_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_HEX16_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_HEX32_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_HEX64_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_PTR_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_STRING_ARRAY (expected, actual, num_elements)` - -##### `TEST_ASSERT_EQUAL_MEMORY_ARRAY (expected, actual, len, num_elements)` - -`len` is the memory in bytes to be compared at each array element. - - -### Each Equal (Arrays to Single Value) - -`expected` are single values and `actual` are arrays. `num_elements` specifies -the number of elements in the arrays to compare. - -`_HEX` assertions produce failure messages with expected and actual array -contents formatted in hexadecimal. - -Assertions fail upon the first element in the compared arrays found not to -match. Failure messages specify the array index of the failed comparison. - -#### `TEST_ASSERT_EACH_EQUAL_INT (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_INT8 (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_INT16 (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_INT32 (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_INT64 (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_UINT (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_UINT8 (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_UINT16 (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_UINT32 (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_UINT64 (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_HEX (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_HEX8 (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_HEX16 (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_HEX32 (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_HEX64 (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_PTR (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_STRING (expected, actual, num_elements)` - -#### `TEST_ASSERT_EACH_EQUAL_MEMORY (expected, actual, len, num_elements)` - -`len` is the memory in bytes to be compared at each array element. - - -### Floating Point (If enabled) - -##### `TEST_ASSERT_FLOAT_WITHIN (delta, expected, actual)` - -Asserts that the `actual` value is within +/- `delta` of the `expected` value. -The nature of floating point representation is such that exact evaluations of -equality are not guaranteed. - - -##### `TEST_ASSERT_EQUAL_FLOAT (expected, actual)` - -Asserts that the ?actual?value is "close enough to be considered equal" to the -`expected` value. If you are curious about the details, refer to the Advanced -Asserting section for more details on this. Omitting a user-specified delta in a -floating point assertion is both a shorthand convenience and a requirement of -code generation conventions for CMock. - - -##### `TEST_ASSERT_EQUAL_FLOAT_ARRAY (expected, actual, num_elements)` - -See Array assertion section for details. Note that individual array element -float comparisons are executed using T?EST_ASSERT_EQUAL_FLOAT?.That is, user -specified delta comparison values requires a custom-implemented floating point -array assertion. - - -##### `TEST_ASSERT_FLOAT_IS_INF (actual)` - -Asserts that `actual` parameter is equivalent to positive infinity floating -point representation. - - -##### `TEST_ASSERT_FLOAT_IS_NEG_INF (actual)` - -Asserts that `actual` parameter is equivalent to negative infinity floating -point representation. - - -##### `TEST_ASSERT_FLOAT_IS_NAN (actual)` - -Asserts that `actual` parameter is a Not A Number floating point representation. - - -##### `TEST_ASSERT_FLOAT_IS_DETERMINATE (actual)` - -Asserts that ?actual?parameter is a floating point representation usable for -mathematical operations. That is, the `actual` parameter is neither positive -infinity nor negative infinity nor Not A Number floating point representations. - - -##### `TEST_ASSERT_FLOAT_IS_NOT_INF (actual)` - -Asserts that `actual` parameter is a value other than positive infinity floating -point representation. - - -##### `TEST_ASSERT_FLOAT_IS_NOT_NEG_INF (actual)` - -Asserts that `actual` parameter is a value other than negative infinity floating -point representation. - - -##### `TEST_ASSERT_FLOAT_IS_NOT_NAN (actual)` - -Asserts that `actual` parameter is a value other than Not A Number floating -point representation. - - -##### `TEST_ASSERT_FLOAT_IS_NOT_DETERMINATE (actual)` - -Asserts that `actual` parameter is not usable for mathematical operations. That -is, the `actual` parameter is either positive infinity or negative infinity or -Not A Number floating point representations. - - -### Double (If enabled) - -##### `TEST_ASSERT_DOUBLE_WITHIN (delta, expected, actual)` - -Asserts that the `actual` value is within +/- `delta` of the `expected` value. -The nature of floating point representation is such that exact evaluations of -equality are not guaranteed. - - -##### `TEST_ASSERT_EQUAL_DOUBLE (expected, actual)` - -Asserts that the `actual` value is "close enough to be considered equal" to the -`expected` value. If you are curious about the details, refer to the Advanced -Asserting section for more details. Omitting a user-specified delta in a -floating point assertion is both a shorthand convenience and a requirement of -code generation conventions for CMock. - - -##### `TEST_ASSERT_EQUAL_DOUBLE_ARRAY (expected, actual, num_elements)` - -See Array assertion section for details. Note that individual array element -double comparisons are executed using `TEST_ASSERT_EQUAL_DOUBLE`.That is, user -specified delta comparison values requires a custom implemented double array -assertion. - - -##### `TEST_ASSERT_DOUBLE_IS_INF (actual)` - -Asserts that `actual` parameter is equivalent to positive infinity floating -point representation. - - -##### `TEST_ASSERT_DOUBLE_IS_NEG_INF (actual)` - -Asserts that `actual` parameter is equivalent to negative infinity floating point -representation. - - -##### `TEST_ASSERT_DOUBLE_IS_NAN (actual)` - -Asserts that `actual` parameter is a Not A Number floating point representation. - - -##### `TEST_ASSERT_DOUBLE_IS_DETERMINATE (actual)` - -Asserts that `actual` parameter is a floating point representation usable for -mathematical operations. That is, the ?actual?parameter is neither positive -infinity nor negative infinity nor Not A Number floating point representations. - - -##### `TEST_ASSERT_DOUBLE_IS_NOT_INF (actual)` - -Asserts that `actual` parameter is a value other than positive infinity floating -point representation. - - -##### `TEST_ASSERT_DOUBLE_IS_NOT_NEG_INF (actual)` - -Asserts that `actual` parameter is a value other than negative infinity floating -point representation. - - -##### `TEST_ASSERT_DOUBLE_IS_NOT_NAN (actual)` - -Asserts that `actual` parameter is a value other than Not A Number floating -point representation. - - -##### `TEST_ASSERT_DOUBLE_IS_NOT_DETERMINATE (actual)` - -Asserts that `actual` parameter is not usable for mathematical operations. That -is, the `actual` parameter is either positive infinity or negative infinity or -Not A Number floating point representations. - - -## Advanced Asserting: Details On Tricky Assertions - -This section helps you understand how to deal with some of the trickier -assertion situations you may run into. It will give you a glimpse into some of -the under-the-hood details of Unity's assertion mechanisms. If you're one of -those people who likes to know what is going on in the background, read on. If -not, feel free to ignore the rest of this document until you need it. - - -### How do the EQUAL assertions work for FLOAT and DOUBLE? - -As you may know, directly checking for equality between a pair of floats or a -pair of doubles is sloppy at best and an outright no-no at worst. Floating point -values can often be represented in multiple ways, particularly after a series of -operations on a value. Initializing a variable to the value of 2.0 is likely to -result in a floating point representation of 2 x 20,but a series of -mathematical operations might result in a representation of 8 x 2-2 -that also evaluates to a value of 2. At some point repeated operations cause -equality checks to fail. - -So Unity doesn't do direct floating point comparisons for equality. Instead, it -checks if two floating point values are "really close." If you leave Unity -running with defaults, "really close" means "within a significant bit or two." -Under the hood, `TEST_ASSERT_EQUAL_FLOAT` is really `TEST_ASSERT_FLOAT_WITHIN` -with the `delta` parameter calculated on the fly. For single precision, delta is -the expected value multiplied by 0.00001, producing a very small proportional -range around the expected value. - -If you are expecting a value of 20,000.0 the delta is calculated to be 0.2. So -any value between 19,999.8 and 20,000.2 will satisfy the equality check. This -works out to be roughly a single bit of range for a single-precision number, and -that's just about as tight a tolerance as you can reasonably get from a floating -point value. - -So what happens when it's zero? Zero - even more than other floating point -values - can be represented many different ways. It doesn't matter if you have -0 x 20 or 0 x 263.It's still zero, right? Luckily, if you -subtract these values from each other, they will always produce a difference of -zero, which will still fall between 0 plus or minus a delta of 0. So it still -works! - -Double precision floating point numbers use a much smaller multiplier, again -approximating a single bit of error. - -If you don't like these ranges and you want to make your floating point equality -assertions less strict, you can change these multipliers to whatever you like by -defining UNITY_FLOAT_PRECISION and UNITY_DOUBLE_PRECISION. See Unity -documentation for more. - - -### How do we deal with targets with non-standard int sizes? - -It's "fun" that C is a standard where something as fundamental as an integer -varies by target. According to the C standard, an `int` is to be the target's -natural register size, and it should be at least 16-bits and a multiple of a -byte. It also guarantees an order of sizes: - -```C -char <= short <= int <= long <= long long -``` - -Most often, `int` is 32-bits. In many cases in the embedded world, `int` is -16-bits. There are rare microcontrollers out there that have 24-bit integers, -and this remains perfectly standard C. - -To make things even more interesting, there are compilers and targets out there -that have a hard choice to make. What if their natural register size is 10-bits -or 12-bits? Clearly they can't fulfill _both_ the requirement to be at least -16-bits AND the requirement to match the natural register size. In these -situations, they often choose the natural register size, leaving us with -something like this: - -```C -char (8 bit) <= short (12 bit) <= int (12 bit) <= long (16 bit) -``` - -Um... yikes. It's obviously breaking a rule or two... but they had to break SOME -rules, so they made a choice. - -When the C99 standard rolled around, it introduced alternate standard-size types. -It also introduced macros for pulling in MIN/MAX values for your integer types. -It's glorious! Unfortunately, many embedded compilers can't be relied upon to -use the C99 types (Sometimes because they have weird register sizes as described -above. Sometimes because they don't feel like it?). - -A goal of Unity from the beginning was to support every combination of -microcontroller or microprocessor and C compiler. Over time, we've gotten really -close to this. There are a few tricks that you should be aware of, though, if -you're going to do this effectively on some of these more idiosyncratic targets. - -First, when setting up Unity for a new target, you're going to want to pay -special attention to the macros for automatically detecting types -(where available) or manually configuring them yourself. You can get information -on both of these in Unity's documentation. - -What about the times where you suddenly need to deal with something odd, like a -24-bit `int`? The simplest solution is to use the next size up. If you have a -24-bit `int`, configure Unity to use 32-bit integers. If you have a 12-bit -`int`, configure Unity to use 16 bits. There are two ways this is going to -affect you: - -1. When Unity displays errors for you, it's going to pad the upper unused bits -with zeros. -2. You're going to have to be careful of assertions that perform signed -operations, particularly `TEST_ASSERT_INT_WITHIN`.Such assertions might wrap -your `int` in the wrong place, and you could experience false failures. You can -always back down to a simple `TEST_ASSERT` and do the operations yourself. - - -*Find The Latest of This And More at [ThrowTheSwitch.org](https://throwtheswitch.org)* |