test_suite_spec.lyx 11.5 KB
 Geert Stappers committed Jul 22, 2018 1 2 #LyX 1.3 created this file. For more info see http://www.lyx.org/ \lyxformat 221  Geert Stappers committed Jul 22, 2018 3 4 5 6 7 8 9 10 11 12 13 14 15 16 \textclass article \begin_preamble \usepackage{url} \end_preamble \language english \inputencoding auto \fontscheme times \graphics default \paperfontsize default \spacing single \papersize Default \paperpackage a4 \use_geometry 0 \use_amsmath 0  Geert Stappers committed Jul 22, 2018 17 18 \use_natbib 0 \use_numerical_citations 0  Geert Stappers committed Jul 22, 2018 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 \paperorientation portrait \secnumdepth 3 \tocdepth 3 \paragraph_separation indent \defskip medskip \quotes_language english \quotes_times 2 \papercolumns 1 \papersides 1 \paperpagestyle default \layout Title Proposed Test Suite Design \layout Author Michael Hope (michaelh@juju.net.nz) \layout Date  Geert Stappers committed Jul 22, 2018 39 40 41 42 \begin_inset ERT status Collapsed \layout Standard  Geert Stappers committed Jul 22, 2018 43 44 45  \backslash today{}  Geert Stappers committed Jul 22, 2018 46 47 48 \end_inset  Geert Stappers committed Jul 22, 2018 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 \layout Abstract This article describes the goals, requirements, and suggested specification for a test suite for the output of the Small Device C Compiler (sdcc). Also included is a short list of existing works. \layout Section Goals \layout Standard The main goals of a test suite for sdcc are \layout Enumerate To allow developers to run regression tests to check that core changes do not break any of the many ports. \layout Enumerate To verify the core. \layout Enumerate To allow developers to verify individual ports. \layout Enumerate To allow developers to test port changes. \layout Standard This design only covers the generated code. It does not cover a test/unit test framework for the sdcc application itself, which may be useful. \layout Standard One side effect of (1) is that it requires that the individual ports pass the tests originally. This may be too hard. See the section on Exceptions below. \layout Section Requirements \layout Subsection Coverage \layout Standard The suite is intended to cover language features only. Hardware specific libraries are explicitly not covered. \layout Subsection Permutations \layout Standard The ports often generate different code for handling different types (Byte, Word, DWord, and the signed forms). Meta information could be used to permute the different test cases across the different types. \layout Subsection Exceptions \layout Standard The different ports are all at different levels of development. Test cases must be able to be disabled on a per port basis. Permutations also must be able to be disabled on a port level for unsupported cases. Disabling, as opposed to enabling, on a per port basis seems more maintainable. \layout Subsection Running \layout Standard The tests must be able to run unaided. The test suite must run on all platforms that sdcc runs on. A good minimum may be a subset of Unix command set and common tools, provided by default on a Unix host and provided through cygwin on a Windows host. \layout Standard The tests suits should be able to be sub-divided, so that the failing or interesting tests may be run separately. \layout Subsection Artifcats \layout Standard The test code within the test cases should not generate artifacts. An artifact occurs when the test code itself interferes with the test and generates an erroneous result. \layout Subsection Emulators \layout Standard sdcc is a cross compiling compiler. As such, an emulator is needed for each port to run the tests. \layout Section Existing works \layout Subsection DejaGnu \layout Standard DejaGnu is a toolkit written in Expect designed to test an interactive program. It provides a way of specifying an interface to the program, and given that interface a way of stimulating the program and interpreting the results. It was originally written by Cygnus Solutions for running against development boards. I believe the gcc test suite is written against DejaGnu, perhaps partly to test the Cygnus ports of gcc on target systems. \layout Subsection gcc test suite \layout Standard I don't know much about the gcc test suite. It was recently removed from the gcc distribution due to issues with copyright ownership. The code I saw from older distributions seemed more concerned with esoteric features of the language. \layout Subsection xUnit \layout Standard The xUnit family, in particular JUnit, is a library of in test assertions, test wrappers, and test suite wrappers designed mainly for unit testing. PENDING: More. \layout Subsection CoreLinux++ Assertion framework \layout Standard While not a test suite system, the assertion framework is an interesting model for the types of assertions that could be used. They include pre-condition, post-condition, invariants, conditional assertions, unconditional assertions, and methods for checking conditions. \layout Section Specification \layout Standard This specification borrows from the JUnit style of unit testing and the CoreLinux++ style of assertions. The emphasis is on maintainability and ease of writing the test cases. \layout Subsection Terms \layout Standard PENDING: Align these terms with the rest of the world. \layout Itemize An \emph on assertion \emph default is a statement of how things should be. PENDING: Better description, an example. \layout Itemize A \emph on test point \emph default is the smallest unit of a test suite, and consists of a single assertion that passes if the test passes. \layout Itemize A \emph on test case \emph default is a set of test points that test a certain feature. \layout Itemize A \emph on test suite \emph default is a set of test cases that test a certain set of features. \layout Subsection Test cases \layout Standard Test cases shall be contained in their own C file, along with the meta data on the test. Test cases shall be contained within functions whose names start with 'test' and which are descriptive of the test case. Any function that starts with 'test' will be automatically run in the test suite. \layout Standard To make the automatic code generation easier, the C code shall have this format \layout Itemize Test functions shall start with 'test' to allow automatic detection. \layout Itemize Test functions shall follow the K&R intention style for ease of detection. i.e. the function name shall start in the left column on a new line below the return specification. \layout Subsection Assertions \layout Standard All assertions shall log the line number, function name, and test case file when they fail. Most assertions can have a more descriptive message attached to them. Assertions will be implemented through macros to get at the line information. This may cause trouble with artifacts. \layout Standard The following definitions use C++ style default arguments where optional messages may be inserted. All assertions use double opening and closing brackets in the macros to allow them to be compiled out without any side effects. While this is not required for a test suite, they are there in case any of this code is incorporated into the main product. \layout Standard Borrowing from JUnit, the assertions shall include \layout Itemize FAIL((String msg = \begin_inset Quotes eld \end_inset Failed \begin_inset Quotes erd \end_inset )). Used when execution should not get here. \layout Itemize ASSERT((Boolean cond, String msg = \begin_inset Quotes eld \end_inset Assertion failed \begin_inset Quotes erd \end_inset ). Fails if cond is false. Parent to REQUIRE and ENSURE. \layout Standard JUnit also includes may sub-cases of ASSERT, such as assertNotNull, assertEquals , and assertSame. \layout Standard CoreLinux++ includes the extra assertions \layout Itemize REQUIRE((Boolean cond, String msg = \begin_inset Quotes eld \end_inset Precondition failed \begin_inset Quotes erd \end_inset ). Checks preconditions. \layout Itemize ENSURE((Boolean cond, String msg = \begin_inset Quotes eld \end_inset Postcondition failed \begin_inset Quotes erd \end_inset ). Checks post conditions. \layout Itemize CHECK((Boolean cond, String msg = \begin_inset Quotes eld \end_inset Check failed \begin_inset Quotes erd \end_inset )). Used to call a function and to check that the return value is as expected. i.e. CHECK((fread(in, buf, 10) != -1)). Very similar to ASSERT, but the function still gets called in a release build. \layout Itemize FORALL and EXISTS. Used to check conditions within part of the code. For example, can be used to check that a list is still sorted inside each loop of a sort routine. \layout Standard All of FAIL, ASSERT, REQUIRE, ENSURE, and CHECK shall be available. \layout Subsection Meta data \layout Standard PENDING: It's not really meta data. \layout Standard Meta data includes permutation information, exception information, and permutati on exceptions. \layout Standard Meta data shall be global to the file. Meta data names consist of the lower case alphanumerics. Test case specific meta data (fields) shall be stored in a comment block at the start of the file. This is only due to style. \layout Standard A field definition shall consist of \layout Itemize The field name \layout Itemize A colon. \layout Itemize A comma separated list of values. \layout Standard The values shall be stripped of leading and trailing white space. \layout Standard Permutation exceptions are by port only. Exceptions to a field are specified by a modified field definition. An exception definition consists of \layout Itemize The field name. \layout Itemize An opening square bracket. \layout Itemize A comma separated list of ports the exception applies for. \layout Itemize A closing square bracket. \layout Itemize A colon. \layout Itemize The values to use for this field for these ports. \layout Standard An instance of the test case shall be generated for each permutation of the test case specific meta data fields. \layout Standard The runtime meta fields are \layout Itemize port - The port this test is running on. \layout Itemize testcase - The name of this test case. \layout Itemize function - The name of the current function. \layout Standard Most of the runtime fields are not very usable. They are there for completeness. \layout Standard Meta fields may be accessed inside the test case by enclosing them in curly brackets. The curly brackets will be interpreted anywhere inside the test case, including inside quoted strings. Field names that are not recognised will be passed through including the brackets. Note that it is therefore impossible to use some strings within the test case. \layout Standard Test case function names should include the permuted fields in the name to reduce name collisions. \layout Subsection An example \layout Standard I don't know how to do pre-formatted text in LaTeX. Sigh. \layout Standard The following code generates a simple increment test for all combinations of the storage classes and all combinations of the data sizes. This is a bad example as the optimiser will often remove most of this code. \layout Standard \family typewriter /** Test for increment. \layout Standard \family typewriter type: char, int, long \layout Standard \family typewriter Z80 port does not fully support longs (4 byte) \layout Standard \family typewriter type[z80]: char, int \layout Standard \family typewriter class: \begin_inset Quotes eld \end_inset \begin_inset Quotes erd \end_inset , register, static */ \layout Standard \family typewriter static void \layout Standard \family typewriter testInc{class}{types}(void) \layout Standard \family typewriter { \layout Standard \family typewriter {class} {type} i = 0; \layout Standard \family typewriter i = i + 1; \layout Standard \family typewriter ASSERT((i == 1)); \layout Standard \family typewriter } \the_end