This repository contains seven tools:

• diff_dbf compares dBase database files (.dbf file extension).
• diff_gv compares files in Graphviz dot language.
• diff_shp compares shapefiles.
• max_diff_rect compares CSV files.
• nccmp compares NetCDF files.
• selective_diff compares directories.
• test_compare launches user-defined processes and compares results with previous runs.

Each of these tools can be run directly on the command line. Some of them call others from this repository.

selective_diff

selective_diff compares two directories, recursively. The value of selective_diff is that it has better than diff capabilities for some chosen types of files: NetCDF, numeric CSV, shapefile.

Note that arguments should be two directories, not two files.

Dependencies: see requirements, plus ndiff.

test_compare

Test code and compare results.

This program chains runs in directories which do not pre-exist and are created.

This program reads a JSON test description file. The test description file must contain a dictionary. The keys of this dictionary should be the titles of the test. Each title is a string and is used as directory name. The value for each title is a dictionary describing a run. Each run is defined by commands, required files (that is, files required to be present in the current directory at run time), environment, stdin filename or input, and stdout filename. Each dictionary must thus include either the key command or commands, and may also include the keys:

main_command, description, stdout, symlink, copy, env, either stdin_filename or input, create_file, sel_diff_args

commands is a list of commands, command is a single command. A command is a list of strings or a single string. If the command is a single string then it is split at whitespace. (The command includes the executable file.)

main_command should be an integer value giving the 0-based index of the main command in the list commands. If main_command is absent and commands is present then the last command is defined as the main command. The only difference between the main command and other commands is that env, stdin_filename and input apply to the main command only.

The standard output of all the commands is redirected to the file pointed by stdout.

The difference between the keys stdin_filename and input is that input must be the content of standard input and stdin_filename must be the name of a file that will be redirected to standard input. stdin_filename may be a relative path: it is evaluated after changing directory to the directory of the test. stdin_filename may be the file created by create_file: it is opened after creating the file. The value of input is passed through to the input keyword argument of subprocess.run. Usually, the value of input should end with \n. If neither stdin_filename nor input is present, then we assume that the run does not need any input: no interaction is allowed.

create_file is a list of two elements: the name of the file to create and its content. The name of the file will normally be a relative path and the file will be created in the directory of the test.

If present, symlink or copy must be a list. Each element of symlink or copy must itself be a string or a list of two strings (no tuple allowed in JSON). If an element of symlink or copy is a string then it must be the absolute path to a file or directory that will be sym-linked or copied to the test directory, with the same basename. It may contain a shell pattern. If a required element is a list of two strings then the first string must be the absolute path to a file or directory that will be sym-linked or copied to the test directory, with the second string as basename. symlink and copy can both be present in a given test description. Generally, files or directories which will not be modified by the test should be sym-linked.

If present, env must be a dictionary of environment variables and values. This dictionary will be added to, not replace, the inherited environment. If an environment variable in env was already in the environment, the value in env replaces the old value. This environment is applied only to the main command.

If stdout is not present then the file name for standard output is constructed from the name of the main command (determined by main_command).

If present, sel_diff_args must be a dictionary. The keys must be arguments of the function selective_diff.

The required files and executables must be specified in the JSON input file with absolute paths. File arguments in commands, if any, also have to be specified with absolute paths.

This program can also read a JSON file containing string substitutions to be made in the test description file. This is useful to abbreviate paths that occur repeatedly in test description file, or to make the test description file independant of the machine. This abbreviation file must contain a single dictionary. The strings $PWD and $tests_old_dir will be automatically substituted in the test description file, they should not be specified in the file containing string substitutions.

There may be several JSON test description files on the command line. If two tests have the same title, the last one will be kept.