| // Copyright 2018 The Bazel Authors. All rights reserved. | |
| // | |
| // Licensed under the Apache License, Version 2.0 (the "License"); | |
| // you may not use this file except in compliance with the License. | |
| // You may obtain a copy of the License at | |
| // | |
| // http://www.apache.org/licenses/LICENSE-2.0 | |
| // | |
| // Unless required by applicable law or agreed to in writing, software | |
| // distributed under the License is distributed on an "AS IS" BASIS, | |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
| // See the License for the specific language governing permissions and | |
| // limitations under the License. | |
| package com.google.devtools.build.lib.skylarkbuildapi; | |
| import com.google.devtools.build.lib.cmdline.Label; | |
| import com.google.devtools.build.lib.events.Location; | |
| import com.google.devtools.build.lib.skylarkinterface.Param; | |
| import com.google.devtools.build.lib.skylarkinterface.ParamType; | |
| import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable; | |
| import com.google.devtools.build.lib.skylarkinterface.SkylarkConstructor; | |
| import com.google.devtools.build.lib.skylarkinterface.SkylarkGlobalLibrary; | |
| import com.google.devtools.build.lib.syntax.BaseFunction; | |
| import com.google.devtools.build.lib.syntax.Environment; | |
| import com.google.devtools.build.lib.syntax.EvalException; | |
| import com.google.devtools.build.lib.syntax.FuncallExpression; | |
| import com.google.devtools.build.lib.syntax.SkylarkDict; | |
| import com.google.devtools.build.lib.syntax.SkylarkList; | |
| /** | |
| * Interface for a global Skylark library containing rule-related helper and registration functions. | |
| */ | |
| @SkylarkGlobalLibrary | |
| public interface SkylarkRuleFunctionsApi<FileApiT extends FileApi> { | |
| @SkylarkCallable( | |
| name = "provider", | |
| doc = | |
| "Creates a declared provider 'constructor'. The return value of this " | |
| + "function can be used to create \"struct-like\" values. Example:<br>" | |
| + "<pre class=\"language-python\">data = provider()\n" | |
| + "d = data(x = 2, y = 3)\n" | |
| + "print(d.x + d.y) # prints 5</pre>", | |
| parameters = { | |
| @Param( | |
| name = "doc", | |
| type = String.class, | |
| legacyNamed = true, | |
| defaultValue = "''", | |
| doc = | |
| "A description of the provider that can be extracted by documentation generating tools." | |
| ), | |
| @Param( | |
| name = "fields", | |
| doc = "If specified, restricts the set of allowed fields. <br>" | |
| + "Possible values are:" | |
| + "<ul>" | |
| + " <li> list of fields:<br>" | |
| + " <pre class=\"language-python\">provider(fields = ['a', 'b'])</pre><p>" | |
| + " <li> dictionary field name -> documentation:<br>" | |
| + " <pre class=\"language-python\">provider(\n" | |
| + " fields = { 'a' : 'Documentation for a', 'b' : 'Documentation for b' })</pre>" | |
| + "</ul>" | |
| + "All fields are optional.", | |
| allowedTypes = { | |
| @ParamType(type = SkylarkList.class, generic1 = String.class), | |
| @ParamType(type = SkylarkDict.class) | |
| }, | |
| noneable = true, | |
| named = true, | |
| positional = false, | |
| defaultValue = "None" | |
| ) | |
| }, | |
| useLocation = true | |
| ) | |
| public ProviderApi provider(String doc, Object fields, Location location) throws EvalException; | |
| @SkylarkCallable( | |
| name = "rule", | |
| doc = | |
| "Creates a new rule, which can be called from a BUILD file or a macro to create targets." | |
| + "<p>Rules must be assigned to global variables in a .bzl file; the name of the " | |
| + "global variable is the rule's name." | |
| + "<p>Test rules are required to have a name ending in <code>_test</code>, while all " | |
| + "other rules must not have this suffix. (This restriction applies only to rules, not " | |
| + "to their targets.)", | |
| parameters = { | |
| @Param( | |
| name = "implementation", | |
| type = BaseFunction.class, | |
| legacyNamed = true, | |
| doc = | |
| "the function implementing this rule, must have exactly one parameter: " | |
| + "<a href=\"ctx.html\">ctx</a>. The function is called during the analysis " | |
| + "phase for each instance of the rule. It can access the attributes " | |
| + "provided by the user. It must create actions to generate all the declared " | |
| + "outputs." | |
| ), | |
| @Param( | |
| name = "test", | |
| type = Boolean.class, | |
| legacyNamed = true, | |
| defaultValue = "False", | |
| doc = | |
| "Whether this rule is a test rule, that is, whether it may be the subject of a " | |
| + "<code>blaze test</code> command. All test rules are automatically considered " | |
| + "<a href='#rule.executable'>executable</a>; it is unnecessary (and discouraged) " | |
| + "to explicitly set <code>executable = True</code> for a test rule. See the " | |
| + "<a href='../rules.$DOC_EXT#executable-rules-and-test-rules'>Rules page</a> for " | |
| + "more information." | |
| ), | |
| @Param( | |
| name = "attrs", | |
| type = SkylarkDict.class, | |
| legacyNamed = true, | |
| noneable = true, | |
| defaultValue = "None", | |
| doc = | |
| "dictionary to declare all the attributes of the rule. It maps from an attribute " | |
| + "name to an attribute object (see <a href=\"attr.html\">attr</a> module). " | |
| + "Attributes starting with <code>_</code> are private, and can be used to " | |
| + "add an implicit dependency on a label. The attribute <code>name</code> is " | |
| + "implicitly added and must not be specified. Attributes " | |
| + "<code>visibility</code>, <code>deprecation</code>, <code>tags</code>, " | |
| + "<code>testonly</code>, and <code>features</code> are implicitly added and " | |
| + "cannot be overridden." | |
| ), | |
| // TODO(bazel-team): need to give the types of these builtin attributes | |
| @Param( | |
| name = "outputs", | |
| type = SkylarkDict.class, | |
| legacyNamed = true, | |
| callbackEnabled = true, | |
| noneable = true, | |
| defaultValue = "None", | |
| doc = | |
| "<b>Experimental:</b> This API is in the process of being redesigned." | |
| + "<p>A schema for defining predeclared outputs. Unlike <a href='attr.html#output'>" | |
| + "<code>output</code></a> and <a href='attr.html#output_list'><code>output_list" | |
| + "</code></a> attributes, the user does not specify the labels for these files. " | |
| + "See the <a href='../rules.$DOC_EXT#files'>Rules page</a> for more on " | |
| + "predeclared outputs." | |
| + "<p>The value of this argument is either a dictionary or a callback function " | |
| + "that produces a dictionary. The callback works similar to computed dependency " | |
| + "attributes: The function's parameter names are matched against the rule's " | |
| + "attributes, so for example if you pass <code>outputs = _my_func</code> with the " | |
| + "definition <code>def _my_func(srcs, deps): ...</code>, the function has access " | |
| + "to the attributes <code>srcs</code> and <code>deps</code>. Whether the " | |
| + "dictionary is specified directly or via a function, it is interpreted as " | |
| + "follows." | |
| + "<p>Each entry in the dictionary creates a predeclared output where the key is " | |
| + "an identifier and the value is a string template that determines the output's " | |
| + "label. In the rule's implementation function, the identifier becomes the field " | |
| + "name used to access the output's <a href='File.html'><code>File</code></a> in " | |
| + "<a href='ctx.html#outputs'><code>ctx.outputs</code></a>. The output's label has " | |
| + "the same package as the rule, and the part after the package is produced by " | |
| + "substituting each placeholder of the form <code>\"%{ATTR}\"</code> with a " | |
| + "string formed from the value of the attribute <code>ATTR</code>:" | |
| + "<ul>" | |
| + "<li>String-typed attributes are substituted verbatim." | |
| + "<li>Label-typed attributes become the part of the label after the package, " | |
| + "minus the file extension. For example, the label <code>\"//pkg:a/b.c\"</code> " | |
| + "becomes <code>\"a/b\"</code>." | |
| + "<li>Output-typed attributes become the part of the label after the package, " | |
| + "including the file extension (for the above example, <code>\"a/b.c\"</code>)." | |
| + "<li>All list-typed attributes (for example, <code>attr.label_list</code>) used " | |
| + "in placeholders are required to have <i>exactly one element</i>. Their " | |
| + "conversion is the same as their non-list version (<code>attr.label</code>)." | |
| + "<li>Other attribute types may not appear in placeholders." | |
| + "<li>The special non-attribute placeholders <code>%{dirname}</code> and <code>" | |
| + "%{basename}</code> expand to those parts of the rule's label, excluding its " | |
| + "package. For example, in <code>\"//pkg:a/b.c\"</code>, the dirname is <code>" | |
| + "a</code> and the basename is <code>b.c</code>." | |
| + "</ul>" | |
| + "<p>In practice, the most common substitution placeholder is " | |
| + "<code>\"%{name}\"</code>. For example, for a target named \"foo\", the outputs " | |
| + "dict <code>{\"bin\": \"%{name}.exe\"}</code> predeclares an output named " | |
| + "<code>foo.exe</code> that is accessible in the implementation function as " | |
| + "<code>ctx.outputs.bin</code>." | |
| ), | |
| @Param( | |
| name = "executable", | |
| type = Boolean.class, | |
| legacyNamed = true, | |
| defaultValue = "False", | |
| doc = | |
| "Whether this rule is considered executable, that is, whether it may be the subject of " | |
| + "a <code>blaze run</code> command. See the " | |
| + "<a href='../rules.$DOC_EXT#executable-rules-and-test-rules'>Rules page</a> for " | |
| + "more information." | |
| ), | |
| @Param( | |
| name = "output_to_genfiles", | |
| type = Boolean.class, | |
| legacyNamed = true, | |
| defaultValue = "False", | |
| doc = | |
| "If true, the files will be generated in the genfiles directory instead of the " | |
| + "bin directory. Unless you need it for compatibility with existing rules " | |
| + "(e.g. when generating header files for C++), do not set this flag." | |
| ), | |
| @Param( | |
| name = "fragments", | |
| type = SkylarkList.class, | |
| legacyNamed = true, | |
| generic1 = String.class, | |
| defaultValue = "[]", | |
| doc = | |
| "List of names of configuration fragments that the rule requires " | |
| + "in target configuration." | |
| ), | |
| @Param( | |
| name = "host_fragments", | |
| type = SkylarkList.class, | |
| legacyNamed = true, | |
| generic1 = String.class, | |
| defaultValue = "[]", | |
| doc = | |
| "List of names of configuration fragments that the rule requires " | |
| + "in host configuration." | |
| ), | |
| @Param( | |
| name = "_skylark_testable", | |
| type = Boolean.class, | |
| legacyNamed = true, | |
| defaultValue = "False", | |
| doc = | |
| "<i>(Experimental)</i><br/><br/>" | |
| + "If true, this rule will expose its actions for inspection by rules that " | |
| + "depend on it via an <a href=\"globals.html#Actions\">Actions</a> " | |
| + "provider. The provider is also available to the rule itself by calling " | |
| + "<a href=\"ctx.html#created_actions\">ctx.created_actions()</a>." | |
| + "<br/><br/>" | |
| + "This should only be used for testing the analysis-time behavior of " | |
| + "Skylark rules. This flag may be removed in the future." | |
| ), | |
| @Param( | |
| name = "toolchains", | |
| type = SkylarkList.class, | |
| legacyNamed = true, | |
| generic1 = String.class, | |
| defaultValue = "[]", | |
| doc = | |
| "<i>(Experimental)</i><br/><br/>" | |
| + "If set, the set of toolchains this rule requires. Toolchains will be " | |
| + "found by checking the current platform, and provided to the rule " | |
| + "implementation via <code>ctx.toolchain</code>." | |
| ), | |
| @Param( | |
| name = "doc", | |
| type = String.class, | |
| legacyNamed = true, | |
| defaultValue = "''", | |
| doc = "A description of the rule that can be extracted by documentation generating tools." | |
| ), | |
| @Param( | |
| name = "provides", | |
| type = SkylarkList.class, | |
| named = true, | |
| positional = false, | |
| defaultValue = "[]", | |
| doc = | |
| "A list of providers this rule is guaranteed to provide. " | |
| + "It is an error if a provider is listed here and the rule " | |
| + "implementation function does not return it." | |
| ), | |
| @Param( | |
| name = "execution_platform_constraints_allowed", | |
| type = Boolean.class, | |
| named = true, | |
| positional = false, | |
| defaultValue = "False", | |
| doc = | |
| "If true, a special attribute named <code>exec_compatible_with</code> of " | |
| + "label-list type is added, which must not already exist in " | |
| + "<code>attrs</code>. Targets may use this attribute to specify additional " | |
| + "constraints on the execution platform beyond those given in the " | |
| + "<code>exec_compatible_with</code> argument to <code>rule()</code>." | |
| ), | |
| @Param( | |
| name = "exec_compatible_with", | |
| type = SkylarkList.class, | |
| generic1 = String.class, | |
| named = true, | |
| positional = false, | |
| defaultValue = "[]", | |
| doc = | |
| "A list of constraints on the execution platform that apply to all targets of " | |
| + "this rule type." | |
| ) | |
| }, | |
| useAst = true, | |
| useEnvironment = true | |
| ) | |
| public BaseFunction rule( | |
| BaseFunction implementation, | |
| Boolean test, | |
| Object attrs, | |
| Object implicitOutputs, | |
| Boolean executable, | |
| Boolean outputToGenfiles, | |
| SkylarkList<?> fragments, | |
| SkylarkList<?> hostFragments, | |
| Boolean skylarkTestable, | |
| SkylarkList<String> toolchains, | |
| String doc, | |
| SkylarkList<?> providesArg, | |
| Boolean executionPlatformConstraintsAllowed, | |
| SkylarkList<?> execCompatibleWith, | |
| FuncallExpression ast, | |
| Environment funcallEnv) | |
| throws EvalException; | |
| @SkylarkCallable( | |
| name = "aspect", | |
| doc = | |
| "Creates a new aspect. The result of this function must be stored in a global value. " | |
| + "Please see the <a href=\"../aspects.md\">introduction to Aspects</a> for more " | |
| + "details.", | |
| parameters = { | |
| @Param( | |
| name = "implementation", | |
| type = BaseFunction.class, | |
| legacyNamed = true, | |
| doc = | |
| "the function implementing this aspect. Must have two parameters: " | |
| + "<a href=\"Target.html\">Target</a> (the target to which the aspect is " | |
| + "applied) and <a href=\"ctx.html\">ctx</a>. Attributes of the target are " | |
| + "available via ctx.rule field. The function is called during the analysis " | |
| + "phase for each application of an aspect to a target." | |
| ), | |
| @Param( | |
| name = "attr_aspects", | |
| type = SkylarkList.class, | |
| legacyNamed = true, | |
| generic1 = String.class, | |
| defaultValue = "[]", | |
| doc = "List of attribute names. The aspect propagates along dependencies specified " | |
| + "by attributes of a target with this name. The list can also contain a single " | |
| + "string '*': in that case aspect propagates along all dependencies of a target." | |
| ), | |
| @Param( | |
| name = "attrs", | |
| type = SkylarkDict.class, | |
| legacyNamed = true, | |
| noneable = true, | |
| defaultValue = "None", | |
| doc = "dictionary to declare all the attributes of the aspect. " | |
| + "It maps from an attribute name to an attribute object " | |
| + "(see <a href=\"attr.html\">attr</a> module). " | |
| + "Aspect attributes are available to implementation function as fields of ctx " | |
| + "parameter. Implicit attributes starting with <code>_</code> must have default " | |
| + "values, and have type <code>label</code> or <code>label_list</code>. " | |
| + "Explicit attributes must have type <code>string</code>, and must use the " | |
| + "<code>values</code> restriction. If explicit attributes are present, the " | |
| + "aspect can only be used with rules that have attributes of the same name and " | |
| + "type, with valid values." | |
| ), | |
| @Param( | |
| name = "required_aspect_providers", | |
| type = SkylarkList.class, | |
| legacyNamed = true, | |
| defaultValue = "[]", | |
| doc = "Allow the aspect to inspect other aspects. If the aspect propagates along " | |
| + "a dependency, and the underlying rule sends a different aspect along that " | |
| + "dependency, and that aspect provides one of the providers listed here, this " | |
| + "aspect will see the providers provided by that aspect. " | |
| + "<p>The value should be either a list of providers, or a " | |
| + "list of lists of providers. This aspect will 'see' the underlying aspects " | |
| + "that provide ALL providers from at least ONE of these lists. A single list " | |
| + "of providers will be automatically converted to a list containing one list of " | |
| + "providers." | |
| ), | |
| @Param( | |
| name = "provides", | |
| type = SkylarkList.class, | |
| legacyNamed = true, | |
| defaultValue = "[]", | |
| doc = | |
| "A list of providers this aspect is guaranteed to provide. " | |
| + "It is an error if a provider is listed here and the aspect " | |
| + "implementation function does not return it." | |
| ), | |
| @Param( | |
| name = "fragments", | |
| type = SkylarkList.class, | |
| legacyNamed = true, | |
| generic1 = String.class, | |
| defaultValue = "[]", | |
| doc = | |
| "List of names of configuration fragments that the aspect requires " | |
| + "in target configuration." | |
| ), | |
| @Param( | |
| name = "host_fragments", | |
| type = SkylarkList.class, | |
| legacyNamed = true, | |
| generic1 = String.class, | |
| defaultValue = "[]", | |
| doc = | |
| "List of names of configuration fragments that the aspect requires " | |
| + "in host configuration." | |
| ), | |
| @Param( | |
| name = "toolchains", | |
| type = SkylarkList.class, | |
| legacyNamed = true, | |
| generic1 = String.class, | |
| defaultValue = "[]", | |
| doc = | |
| "<i>(Experimental)</i><br/><br/>" | |
| + "If set, the set of toolchains this rule requires. Toolchains will be " | |
| + "found by checking the current platform, and provided to the rule " | |
| + "implementation via <code>ctx.toolchain</code>." | |
| ), | |
| @Param( | |
| name = "doc", | |
| type = String.class, | |
| legacyNamed = true, | |
| defaultValue = "''", | |
| doc = "A description of the aspect that can be extracted by documentation generating " | |
| + "tools." | |
| ) | |
| }, | |
| useEnvironment = true, | |
| useAst = true | |
| ) | |
| public SkylarkAspectApi aspect( | |
| BaseFunction implementation, | |
| SkylarkList attributeAspects, | |
| Object attrs, | |
| SkylarkList requiredAspectProvidersArg, | |
| SkylarkList providesArg, | |
| SkylarkList fragments, | |
| SkylarkList hostFragments, | |
| SkylarkList<String> toolchains, | |
| String doc, | |
| FuncallExpression ast, | |
| Environment funcallEnv) | |
| throws EvalException; | |
| @SkylarkCallable( | |
| name = "Label", | |
| doc = "Creates a Label referring to a BUILD target. Use " | |
| + "this function only when you want to give a default value for the label attributes. " | |
| + "The argument must refer to an absolute label. " | |
| + "Example: <br><pre class=language-python>Label(\"//tools:default\")</pre>", | |
| parameters = { | |
| @Param(name = "label_string", type = String.class, legacyNamed = true, | |
| doc = "the label string."), | |
| @Param( | |
| name = "relative_to_caller_repository", | |
| type = Boolean.class, | |
| defaultValue = "False", | |
| named = true, | |
| positional = false, | |
| doc = "Deprecated. Do not use. " | |
| + "When relative_to_caller_repository is True and the calling thread is a rule's " | |
| + "implementation function, then a repo-relative label //foo:bar is resolved " | |
| + "relative to the rule's repository. For calls to Label from any other " | |
| + "thread, or calls in which the relative_to_caller_repository flag is False, " | |
| + "a repo-relative label is resolved relative to the file in which the " | |
| + "Label() call appears." | |
| ) | |
| }, | |
| useLocation = true, | |
| useEnvironment = true | |
| ) | |
| @SkylarkConstructor(objectType = Label.class) | |
| public Label label( | |
| String labelString, Boolean relativeToCallerRepository, Location loc, Environment env) | |
| throws EvalException; | |
| @SkylarkCallable( | |
| name = "FileType", | |
| doc = | |
| "Deprecated. Creates a file filter from a list of strings. For example, to match " | |
| + "files ending with .cc or .cpp, use: " | |
| + "<pre class=language-python>FileType([\".cc\", \".cpp\"])</pre>", | |
| parameters = { | |
| @Param( | |
| name = "types", | |
| type = SkylarkList.class, | |
| legacyNamed = true, | |
| generic1 = String.class, | |
| defaultValue = "[]", | |
| doc = "a list of the accepted file extensions." | |
| ) | |
| }, | |
| useLocation = true, | |
| useEnvironment = true | |
| ) | |
| @SkylarkConstructor(objectType = FileTypeApi.class) | |
| public FileTypeApi<FileApiT> fileType(SkylarkList<?> types, Location loc, Environment env) | |
| throws EvalException; | |
| } |