Merge pull request #55 from cash/coding-standards

Refs #3657 separate out coding standards. (Still need to redirect requests for CODING.txt)

1 files changed, 36 insertions, 0 deletions

diff --git a/documentation/coding_standards/deprecation.txt b/documentation/coding_standards/deprecation.txt
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+*** DEPRECATING APIs ***
+
+Occasionally, functions and classes must be deprecated in favor of newer
+replacements.  Since 3rd party plugin authors rely on a consistent API,
+backward compatibility must be maintained, but will not be maintained
+indefinitely as plugin authors are expected to properly update their
+plugins.  In order to maintain backward compatibility, deprecated APIs will
+follow these guidelines:
+
+* 	Incompatible API changes cannot occur between bugfix versions
+	(1.6.0 - 1.6.1).
+
+* 	API changes between minor versions (1.6 - 1.7) must maintain backward
+	compatibility for at least 2 minor versions.  (1.7 and 1.8. See
+	procedures, below.)
+
+* 	Bugfixes that change the API cannot be included in bugfix versions.
+
+* 	API changes between major versions (1.0 - 2.0) can occur without regard to
+	backward compatibility.
+
+The procedure for deprecating an API is as follows:
+
+* 	The first minor version (1.7) with a deprecated API must include a wrapper
+	function/class (or otherwise appropriate means) to maintain backward
+	compatibility, including any bugs in the original function/class.
+	This compatibility layer uses elgg_deprecated_notice('...', 1.7) to log
+	that the function is deprecated.
+
+* 	The second minor version (1.8) maintains the backward compatibility
+	layer, but elgg_deprecated_notice() will produce a visible warning.
+
+* 	The third minor version (1.9) removes the compatibility layer.  Any use of
+	the deprecated API should be corrected before this.
+
+The general timeline for two minor releases is 8 to 12 months.