1NPM-DEDUPE(1) NPM-DEDUPE(1)
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6 npm-dedupe - Reduce duplication in the package tree
7 Synopsis
9 npm dedupe
10 alias: ddp
12 Description
14 Searches the local package tree and attempts to simplify the overall
15 structure by moving dependencies further up the tree, where they can be
16 more effectively shared by multiple dependent packages.
17 For example, consider this dependency graph:
19 a
21 +-- b <-- depends on c@1.0.x
22 | `-- c@1.0.3
23 `-- d <-- depends on c@~1.0.9
24 `-- c@1.0.10
25 In this case, npm dedupe will transform the tree to:
27 a
29 +-- b
30 +-- d
31 `-- c@1.0.10
32 Because of the hierarchical nature of node's module lookup, b and d
34 will both get their dependency met by the single c package at the root
35 level of the tree.
36 In some cases, you may have a dependency graph like this:
38 a
40 +-- b <-- depends on c@1.0.x
41 +-- c@1.0.3
42 `-- d <-- depends on c@1.x
43 `-- c@1.9.9
44 During the installation process, the c@1.0.3 dependency for b was
46 placed in the root of the tree. Though d's dependency on c@1.x could
47 have been satisfied by c@1.0.3, the newer c@1.9.0 dependency was used,
48 because npm favors updates by default, even when doing so causes dupli‐
49 cation.
50 Running npm dedupe will cause npm to note the duplication and re-evalu‐
52 ate, deleting the nested c module, because the one in the root is suf‐
53 ficient.
54 To prefer deduplication over novelty during the installation process,
56 run npm install --prefer-dedupe or npm config set prefer-dedupe true.
57 Arguments are ignored. Dedupe always acts on the entire tree.
59 Note that this operation transforms the dependency tree, but will never
61 result in new modules being installed.
62 Using npm find-dupes will run the command in --dry-run mode.
64 Note: npm dedupe will never update the semver values of direct depen‐
66 dencies in your project package.json, if you want to update values in
67 package.json you can run: npm update --save instead.
68 Configuration
70 global-style
71 • Default: false
72 • Type: Boolean
74 Causes npm to install the package into your local node_modules folder
77 with the same layout it uses with the global node_modules folder. Only
78 your direct dependencies will show in node_modules and everything they
79 depend on will be flattened in their node_modules folders. This obvi‐
80 ously will eliminate some deduping. If used with legacy-bundling,
81 legacy-bundling will be preferred.
82 legacy-bundling
84 • Default: false
85 • Type: Boolean
87 Causes npm to install the package such that versions of npm prior to
90 1.4, such as the one included with node 0.8, can install the package.
91 This eliminates all automatic deduping. If used with global-style this
92 option will be preferred.
93 strict-peer-deps
95 • Default: false
96 • Type: Boolean
98 If set to true, and --legacy-peer-deps is not set, then any conflicting
101 peerDependencies will be treated as an install failure, even if npm
102 could reasonably guess the appropriate resolution based on non-peer de‐
103 pendency relationships.
104 By default, conflicting peerDependencies deep in the dependency graph
106 will be resolved using the nearest non-peer dependency specification,
107 even if doing so will result in some packages receiving a peer depen‐
108 dency outside the range set in their package's peerDependencies object.
109 When such and override is performed, a warning is printed, explaining
111 the conflict and the packages involved. If --strict-peer-deps is set,
112 then this warning is treated as a failure.
113 package-lock
115 • Default: true
116 • Type: Boolean
118 If set to false, then ignore package-lock.json files when installing.
121 This will also prevent writing package-lock.json if save is true.
122 This configuration does not affect npm ci.
124 omit
126 • Default: 'dev' if the NODE_ENV environment variable is set to 'pro‐
127 duction', otherwise empty.
128 • Type: "dev", "optional", or "peer" (can be set multiple times)
130 Dependency types to omit from the installation tree on disk.
133 Note that these dependencies are still resolved and added to the pack‐
135 age-lock.json or npm-shrinkwrap.json file. They are just not physically
136 installed on disk.
137 If a package type appears in both the --include and --omit lists, then
139 it will be included.
140 If the resulting omit list includes 'dev', then the NODE_ENV environ‐
142 ment variable will be set to 'production' for all lifecycle scripts.
143 ignore-scripts
145 • Default: false
146 • Type: Boolean
148 If true, npm does not run scripts specified in package.json files.
151 Note that commands explicitly intended to run a particular script, such
153 as npm start, npm stop, npm restart, npm test, and npm run-script will
154 still run their intended script if ignore-scripts is set, but they will
155 not run any pre- or post-scripts.
156 audit
158 • Default: true
159 • Type: Boolean
161 When "true" submit audit reports alongside the current npm command to
164 the default registry and all registries configured for scopes. See the
165 documentation for npm help audit for details on what is submitted.
166 bin-links
168 • Default: true
169 • Type: Boolean
171 Tells npm to create symlinks (or .cmd shims on Windows) for package ex‐
174 ecutables.
175 Set to false to have it not do this. This can be used to work around
177 the fact that some file systems don't support symlinks, even on osten‐
178 sibly Unix systems.
179 fund
181 • Default: true
182 • Type: Boolean
184 When "true" displays the message at the end of each npm install ac‐
187 knowledging the number of dependencies looking for funding. See npm
188 help npm fund for details.
189 dry-run
191 • Default: false
192 • Type: Boolean
194 Indicates that you don't want npm to make any changes and that it
197 should only report what it would have done. This can be passed into any
198 of the commands that modify your local installation, eg, install, up‐
199 date, dedupe, uninstall, as well as pack and publish.
200 Note: This is NOT honored by other network related commands, eg
202 dist-tags, owner, etc.
203 workspace
205 • Default:
206 • Type: String (can be set multiple times)
208 Enable running a command in the context of the configured workspaces of
211 the current project while filtering by running only the workspaces de‐
212 fined by this configuration option.
213 Valid values for the workspace config are either:
215 • Workspace names
217 • Path to a workspace directory
219 • Path to a parent workspace directory (will result in selecting all
221 workspaces within that folder)
222 When set for the npm init command, this may be set to the folder of a
225 workspace which does not yet exist, to create the folder and set it up
226 as a brand new workspace within the project.
227 This value is not exported to the environment for child processes.
229 workspaces
231 • Default: null
232 • Type: null or Boolean
234 Set to true to run the command in the context of all configured
237 workspaces.
238 Explicitly setting this to false will cause commands like install to
240 ignore workspaces altogether. When not set explicitly:
241 • Commands that operate on the node_modules tree (install, update,
243 etc.) will link workspaces into the node_modules folder. - Commands
244 that do other things (test, exec, publish, etc.) will operate on the
245 root project, unless one or more workspaces are specified in the
246 workspace config.
247 This value is not exported to the environment for child processes.
250 include-workspace-root
252 • Default: false
253 • Type: Boolean
255 Include the workspace root when workspaces are enabled for a command.
258 When false, specifying individual workspaces via the workspace config,
260 or all workspaces via the workspaces flag, will cause npm to operate
261 only on the specified workspaces, and not on the root project.
262 This value is not exported to the environment for child processes.
264 install-links
266 • Default: false
267 • Type: Boolean
269 When set file: protocol dependencies that exist outside of the project
272 root will be packed and installed as regular dependencies instead of
273 creating a symlink. This option has no effect on workspaces.
274 See Also
276 • npm help find-dupes
277 • npm help ls
279 • npm help update
281 • npm help install
283 September 2022 NPM-DEDUPE(1)