[Bug] Check if plugin is array before accessing first index

[sserrata]

Description

This change checks that the plugin is defined as an Array before attempting to access the first index.

See #315 for background

Valid plugin config variations:

{
  plugins: [
    ["@docusaurus/plugin-content-docs",options],
    "./myPlugin",
    ["./myPlugin",{someOption: 42}],
    function myPlugin() { },
    [function myPlugin() { },options]
  ],
};

Basically, the getDocsPluginConfig() function previously assumed that plugins would be defined as arrays. Since plugins may also be functions (defined locally) or strings this resulted in an error when we attempted to access the first index.

[github-actions]

Size Change: 0 B

Total Size: 4.01 MB

ℹ️ View Unchanged

Filename	Size
demo/.docusaurus/globalData.json	18.6 kB
demo/build/assets/css/styles.********.css	94.4 kB
demo/build/assets/js/006e727e.********.js	13.9 kB
demo/build/assets/js/05f64ae1.********.js	2.83 kB
demo/build/assets/js/06b64fc1.********.js	575 B
demo/build/assets/js/06e5f0f0.********.js	36.9 kB
demo/build/assets/js/081bfb0d.********.js	10 kB
demo/build/assets/js/09e07b87.********.js	3.01 kB
demo/build/assets/js/0d832478.********.js	26.5 kB
demo/build/assets/js/12693653.********.js	25.7 kB
demo/build/assets/js/14eb3368.********.js	9.28 kB
demo/build/assets/js/1639936b.********.js	7.78 kB
demo/build/assets/js/16577668.********.js	387 B
demo/build/assets/js/177e86db.********.js	11.3 kB
demo/build/assets/js/19d75775.********.js	9.33 kB
demo/build/assets/js/1a8cc2a6.********.js	12.1 kB
demo/build/assets/js/1be78505.********.js	10.6 kB
demo/build/assets/js/1c54f54e.********.js	10.8 kB
demo/build/assets/js/1e6c5cae.********.js	34.8 kB
demo/build/assets/js/1e6ff21d.********.js	10.9 kB
demo/build/assets/js/1f818248.********.js	14.8 kB
demo/build/assets/js/2554.********.js	1.31 MB
demo/build/assets/js/2c860537.********.js	7.91 kB
demo/build/assets/js/3136173c.********.js	361 B
demo/build/assets/js/326c3861.********.js	19.1 kB
demo/build/assets/js/3720c009.********.js	1.44 kB
demo/build/assets/js/3893.********.js	1.07 kB
demo/build/assets/js/3946f914.********.js	34.6 kB
demo/build/assets/js/39d00f16.********.js	19.6 kB
demo/build/assets/js/3e0d14e9.********.js	24.3 kB
demo/build/assets/js/40a238b6.********.js	25.7 kB
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demo/build/assets/js/423cd203.********.js	13.9 kB
demo/build/assets/js/4261.********.js	480 B
demo/build/assets/js/466ac800.********.js	43.8 kB
demo/build/assets/js/46afcded.********.js	8.21 kB
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demo/build/assets/js/47abaca6.********.js	2.92 kB
demo/build/assets/js/4935.********.js	1.05 kB
demo/build/assets/js/4964e910.********.js	25.2 kB
demo/build/assets/js/49bd3d39.********.js	17.4 kB
demo/build/assets/js/4b891ed6.********.js	12 kB
demo/build/assets/js/4b901b1a.********.js	350 B
demo/build/assets/js/4c5e977b.********.js	41.9 kB
demo/build/assets/js/55960ee5.********.js	383 B
demo/build/assets/js/55a6d13f.********.js	14.4 kB
demo/build/assets/js/56717cba.********.js	2.98 kB
demo/build/assets/js/57f1a671.********.js	11.4 kB
demo/build/assets/js/58ff8b1e.********.js	20.7 kB
demo/build/assets/js/597ddc40.********.js	10.5 kB
demo/build/assets/js/5fb917be.********.js	2.64 kB
demo/build/assets/js/63fc267d.********.js	11.4 kB
demo/build/assets/js/66c76a57.********.js	35.5 kB
demo/build/assets/js/68b61ac5.********.js	44.6 kB
demo/build/assets/js/69a61f78.********.js	25.5 kB
demo/build/assets/js/6a105426.********.js	354 B
demo/build/assets/js/73b594ee.********.js	35.2 kB
demo/build/assets/js/77264a1a.********.js	34.5 kB
demo/build/assets/js/7ca3ae45.********.js	17.5 kB
demo/build/assets/js/7ed7dafe.********.js	26.9 kB
demo/build/assets/js/8003.********.js	5.45 kB
demo/build/assets/js/85d3c400.********.js	2.91 kB
demo/build/assets/js/85ec4403.********.js	4.74 kB
demo/build/assets/js/86b273b1.********.js	10.6 kB
demo/build/assets/js/86c346b0.********.js	538 B
demo/build/assets/js/86c45737.********.js	26 kB
demo/build/assets/js/881db345.********.js	394 B
demo/build/assets/js/8961c7a6.********.js	24.9 kB
demo/build/assets/js/8ab9b16e.********.js	10.5 kB
demo/build/assets/js/8d4e78cd.********.js	2.85 kB
demo/build/assets/js/8f441c78.********.js	19 kB
demo/build/assets/js/91696e06.********.js	35 kB
demo/build/assets/js/93304a97.********.js	7.91 kB
demo/build/assets/js/935f2afb.********.js	42.7 kB
demo/build/assets/js/94589c06.********.js	20.4 kB
demo/build/assets/js/967247e2.********.js	8.71 kB
demo/build/assets/js/97810f3c.********.js	25.4 kB
demo/build/assets/js/9b5caaf3.********.js	26.3 kB
demo/build/assets/js/9c42c0f3.********.js	34.5 kB
demo/build/assets/js/a40c6d71.********.js	8.69 kB
demo/build/assets/js/a476e24e.********.js	344 B
demo/build/assets/js/a5491aaa.********.js	400 B
demo/build/assets/js/a6cd895f.********.js	21.2 kB
demo/build/assets/js/a728d93a.********.js	10.1 kB
demo/build/assets/js/aa2f1ec7.********.js	25 kB
demo/build/assets/js/ab09fd5c.********.js	20.7 kB
demo/build/assets/js/ab6072f2.********.js	25.6 kB
demo/build/assets/js/ae7f40a3.********.js	44.1 kB
demo/build/assets/js/b4ebd305.********.js	18 kB
demo/build/assets/js/b5c059ef.********.js	34.1 kB
demo/build/assets/js/bead4b8e.********.js	3.06 kB
demo/build/assets/js/bf271e74.********.js	401 B
demo/build/assets/js/c5644638.********.js	337 B
demo/build/assets/js/c65697f5.********.js	26.3 kB
demo/build/assets/js/c7a5be9f.********.js	10.7 kB
demo/build/assets/js/c7ded1cb.********.js	2.96 kB
demo/build/assets/js/cef3f2e2.********.js	5.8 kB
demo/build/assets/js/cf07762b.********.js	25.6 kB
demo/build/assets/js/common.********.js	386 kB
demo/build/assets/js/d63c7029.********.js	2.94 kB
demo/build/assets/js/dd696920.********.js	25.8 kB
demo/build/assets/js/df203c0f.********.js	1.8 kB
demo/build/assets/js/e015ccf9.********.js	26.3 kB
demo/build/assets/js/e01f8d18.********.js	8.76 kB
demo/build/assets/js/e2ce9793.********.js	402 B
demo/build/assets/js/e5e5340c.********.js	2.55 kB
demo/build/assets/js/e8b309fb.********.js	577 B
demo/build/assets/js/eae14b71.********.js	33.8 kB
demo/build/assets/js/eaf4471e.********.js	12.5 kB
demo/build/assets/js/ecc39b49.********.js	172 B
demo/build/assets/js/ee308fa3.********.js	10.2 kB
demo/build/assets/js/f212caf7.********.js	25.4 kB
demo/build/assets/js/f4486b6b.********.js	12 kB
demo/build/assets/js/f65290a6.********.js	11.1 kB
demo/build/assets/js/f8409a7e.********.js	34.3 kB
demo/build/assets/js/f84e10c2.********.js	19.1 kB
demo/build/assets/js/fe97f0d1.********.js	20 kB
demo/build/assets/js/main.********.js	393 kB
demo/build/assets/js/runtime~main.********.js	8.81 kB
demo/build/index.html	88.3 kB

_{compressed-size-action}

[github-actions]

Visit the preview URL for this PR (updated for commit 27f9c75):

https://docusaurus-openapi-36b86--pr321-tav7oasb.web.app

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[sserrata]

Reviewed the error output in #315 and concluded that all expected cases should be covered:

• ["@docusaurus/plugin-content-docs",options] ✅

• "./myPlugin", ❌ not an array

• ["./myPlugin",{someOption: 42}], ❌ array with string as first index but pattern doesn't match

• function myPlugin() { }, ❌ not an array

• [function myPlugin() { },options] ❌ array with function as first index