More efficient JSON imports

[fabiospampinato]

esbuild seems to transform json imports relatively inefficiently.

Given the following index.ts:

import db from './database.json';

const mime = db;

export default mime;

The following database.json:

```json { "application/andrew-inset": ["ez"], "application/applixware": ["aw"], "application/atom+xml": ["atom"], "application/atomcat+xml": ["atomcat"], "application/atomdeleted+xml": ["atomdeleted"], "application/atomsvc+xml": ["atomsvc"], "application/atsc-dwd+xml": ["dwd"], "application/atsc-held+xml": ["held"], "application/atsc-rsat+xml": ["rsat"], "application/bdoc": ["bdoc"], "application/calendar+xml": ["xcs"], "application/ccxml+xml": ["ccxml"], "application/cdfx+xml": ["cdfx"], "application/cdmi-capability": ["cdmia"], "application/cdmi-container": ["cdmic"], "application/cdmi-domain": ["cdmid"], "application/cdmi-object": ["cdmio"], "application/cdmi-queue": ["cdmiq"], "application/cu-seeme": ["cu"], "application/dash+xml": ["mpd"], "application/davmount+xml": ["davmount"], "application/docbook+xml": ["dbk"], "application/dssc+der": ["dssc"], "application/dssc+xml": ["xdssc"], "application/ecmascript": ["es", "ecma"], "application/emma+xml": ["emma"], "application/emotionml+xml": ["emotionml"], "application/epub+zip": ["epub"], "application/exi": ["exi"], "application/express": ["exp"], "application/fdt+xml": ["fdt"], "application/font-tdpfr": ["pfr"], "application/geo+json": ["geojson"], "application/gml+xml": ["gml"], "application/gpx+xml": ["gpx"], "application/gxf": ["gxf"], "application/gzip": ["gz"], "application/hjson": ["hjson"], "application/hyperstudio": ["stk"], "application/inkml+xml": ["ink", "inkml"], "application/ipfix": ["ipfix"], "application/its+xml": ["its"], "application/java-archive": ["jar", "war", "ear"], "application/java-serialized-object": ["ser"], "application/java-vm": ["class"], "application/javascript": ["js", "mjs"], "application/json": ["json", "map"], "application/json5": ["json5"], "application/jsonml+json": ["jsonml"], "application/ld+json": ["jsonld"], "application/lgr+xml": ["lgr"], "application/lost+xml": ["lostxml"], "application/mac-binhex40": ["hqx"], "application/mac-compactpro": ["cpt"], "application/mads+xml": ["mads"], "application/manifest+json": ["webmanifest"], "application/marc": ["mrc"], "application/marcxml+xml": ["mrcx"], "application/mathematica": ["ma", "nb", "mb"], "application/mathml+xml": ["mathml"], "application/mbox": ["mbox"], "application/mediaservercontrol+xml": ["mscml"], "application/metalink+xml": ["metalink"], "application/metalink4+xml": ["meta4"], "application/mets+xml": ["mets"], "application/mmt-aei+xml": ["maei"], "application/mmt-usd+xml": ["musd"], "application/mods+xml": ["mods"], "application/mp21": ["m21", "mp21"], "application/mp4": ["mp4s", "m4p"], "application/msword": ["doc", "dot"], "application/mxf": ["mxf"], "application/n-quads": ["nq"], "application/n-triples": ["nt"], "application/node": ["cjs"], "application/octet-stream": ["bin", "dms", "lrf", "mar", "so", "dist", "distz", "pkg", "bpk", "dump", "elc", "deploy", "exe", "dll", "deb", "dmg", "iso", "img", "msi", "msp", "msm", "buffer"], "application/oda": ["oda"], "application/oebps-package+xml": ["opf"], "application/ogg": ["ogx"], "application/omdoc+xml": ["omdoc"], "application/onenote": ["onetoc", "onetoc2", "onetmp", "onepkg"], "application/oxps": ["oxps"], "application/p2p-overlay+xml": ["relo"], "application/patch-ops-error+xml": ["xer"], "application/pdf": ["pdf"], "application/pgp-encrypted": ["pgp"], "application/pgp-signature": ["asc", "sig"], "application/pics-rules": ["prf"], "application/pkcs10": ["p10"], "application/pkcs7-mime": ["p7m", "p7c"], "application/pkcs7-signature": ["p7s"], "application/pkcs8": ["p8"], "application/pkix-attr-cert": ["ac"], "application/pkix-cert": ["cer"], "application/pkix-crl": ["crl"], "application/pkix-pkipath": ["pkipath"], "application/pkixcmp": ["pki"], "application/pls+xml": ["pls"], "application/postscript": ["ai", "eps", "ps"], "application/provenance+xml": ["provx"], "application/pskc+xml": ["pskcxml"], "application/raml+yaml": ["raml"], "application/rdf+xml": ["rdf", "owl"], "application/reginfo+xml": ["rif"], "application/relax-ng-compact-syntax": ["rnc"], "application/resource-lists+xml": ["rl"], "application/resource-lists-diff+xml": ["rld"], "application/rls-services+xml": ["rs"], "application/route-apd+xml": ["rapd"], "application/route-s-tsid+xml": ["sls"], "application/route-usd+xml": ["rusd"], "application/rpki-ghostbusters": ["gbr"], "application/rpki-manifest": ["mft"], "application/rpki-roa": ["roa"], "application/rsd+xml": ["rsd"], "application/rss+xml": ["rss"], "application/rtf": ["rtf"], "application/sbml+xml": ["sbml"], "application/scvp-cv-request": ["scq"], "application/scvp-cv-response": ["scs"], "application/scvp-vp-request": ["spq"], "application/scvp-vp-response": ["spp"], "application/sdp": ["sdp"], "application/senml+xml": ["senmlx"], "application/sensml+xml": ["sensmlx"], "application/set-payment-initiation": ["setpay"], "application/set-registration-initiation": ["setreg"], "application/shf+xml": ["shf"], "application/sieve": ["siv", "sieve"], "application/smil+xml": ["smi", "smil"], "application/sparql-query": ["rq"], "application/sparql-results+xml": ["srx"], "application/srgs": ["gram"], "application/srgs+xml": ["grxml"], "application/sru+xml": ["sru"], "application/ssdl+xml": ["ssdl"], "application/ssml+xml": ["ssml"], "application/swid+xml": ["swidtag"], "application/tei+xml": ["tei", "teicorpus"], "application/thraud+xml": ["tfi"], "application/timestamped-data": ["tsd"], "application/toml": ["toml"], "application/trig": ["trig"], "application/ttml+xml": ["ttml"], "application/ubjson": ["ubj"], "application/urc-ressheet+xml": ["rsheet"], "application/urc-targetdesc+xml": ["td"], "application/voicexml+xml": ["vxml"], "application/wasm": ["wasm"], "application/widget": ["wgt"], "application/winhlp": ["hlp"], "application/wsdl+xml": ["wsdl"], "application/wspolicy+xml": ["wspolicy"], "application/xaml+xml": ["xaml"], "application/xcap-att+xml": ["xav"], "application/xcap-caps+xml": ["xca"], "application/xcap-diff+xml": ["xdf"], "application/xcap-el+xml": ["xel"], "application/xcap-ns+xml": ["xns"], "application/xenc+xml": ["xenc"], "application/xhtml+xml": ["xhtml", "xht"], "application/xliff+xml": ["xlf"], "application/xml": ["xml", "xsl", "xsd", "rng"], "application/xml-dtd": ["dtd"], "application/xop+xml": ["xop"], "application/xproc+xml": ["xpl"], "application/xslt+xml": ["*xsl", "xslt"], "application/xspf+xml": ["xspf"], "application/xv+xml": ["mxml", "xhvml", "xvml", "xvm"], "application/yang": ["yang"], "application/yin+xml": ["yin"], "application/zip": ["zip"], "audio/3gpp": ["*3gpp"], "audio/adpcm": ["adp"], "audio/amr": ["amr"], "audio/basic": ["au", "snd"], "audio/midi": ["mid", "midi", "kar", "rmi"], "audio/mobile-xmf": ["mxmf"], "audio/mp3": ["*mp3"], "audio/mp4": ["m4a", "mp4a"], "audio/mpeg": ["mpga", "mp2", "mp2a", "mp3", "m2a", "m3a"], "audio/ogg": ["oga", "ogg", "spx", "opus"], "audio/s3m": ["s3m"], "audio/silk": ["sil"], "audio/wav": ["wav"], "audio/wave": ["*wav"], "audio/webm": ["weba"], "audio/xm": ["xm"], "font/collection": ["ttc"], "font/otf": ["otf"], "font/ttf": ["ttf"], "font/woff": ["woff"], "font/woff2": ["woff2"], "image/aces": ["exr"], "image/apng": ["apng"], "image/avif": ["avif"], "image/bmp": ["bmp"], "image/cgm": ["cgm"], "image/dicom-rle": ["drle"], "image/emf": ["emf"], "image/fits": ["fits"], "image/g3fax": ["g3"], "image/gif": ["gif"], "image/heic": ["heic"], "image/heic-sequence": ["heics"], "image/heif": ["heif"], "image/heif-sequence": ["heifs"], "image/hej2k": ["hej2"], "image/hsj2": ["hsj2"], "image/ief": ["ief"], "image/jls": ["jls"], "image/jp2": ["jp2", "jpg2"], "image/jpeg": ["jpeg", "jpg", "jpe"], "image/jph": ["jph"], "image/jphc": ["jhc"], "image/jpm": ["jpm"], "image/jpx": ["jpx", "jpf"], "image/jxr": ["jxr"], "image/jxra": ["jxra"], "image/jxrs": ["jxrs"], "image/jxs": ["jxs"], "image/jxsc": ["jxsc"], "image/jxsi": ["jxsi"], "image/jxss": ["jxss"], "image/ktx": ["ktx"], "image/ktx2": ["ktx2"], "image/png": ["png"], "image/sgi": ["sgi"], "image/svg+xml": ["svg", "svgz"], "image/t38": ["t38"], "image/tiff": ["tif", "tiff"], "image/tiff-fx": ["tfx"], "image/webp": ["webp"], "image/wmf": ["wmf"], "message/disposition-notification": ["disposition-notification"], "message/global": ["u8msg"], "message/global-delivery-status": ["u8dsn"], "message/global-disposition-notification": ["u8mdn"], "message/global-headers": ["u8hdr"], "message/rfc822": ["eml", "mime"], "model/3mf": ["3mf"], "model/gltf+json": ["gltf"], "model/gltf-binary": ["glb"], "model/iges": ["igs", "iges"], "model/mesh": ["msh", "mesh", "silo"], "model/mtl": ["mtl"], "model/obj": ["obj"], "model/step+xml": ["stpx"], "model/step+zip": ["stpz"], "model/step-xml+zip": ["stpxz"], "model/stl": ["stl"], "model/vrml": ["wrl", "vrml"], "model/x3d+binary": ["*x3db", "x3dbz"], "model/x3d+fastinfoset": ["x3db"], "model/x3d+vrml": ["*x3dv", "x3dvz"], "model/x3d+xml": ["x3d", "x3dz"], "model/x3d-vrml": ["x3dv"], "text/cache-manifest": ["appcache", "manifest"], "text/calendar": ["ics", "ifb"], "text/coffeescript": ["coffee", "litcoffee"], "text/css": ["css"], "text/csv": ["csv"], "text/html": ["html", "htm", "shtml"], "text/jade": ["jade"], "text/jsx": ["jsx"], "text/less": ["less"], "text/markdown": ["markdown", "md"], "text/mathml": ["mml"], "text/mdx": ["mdx"], "text/n3": ["n3"], "text/plain": ["txt", "text", "conf", "def", "list", "log", "in", "ini"], "text/richtext": ["rtx"], "text/rtf": ["*rtf"], "text/sgml": ["sgml", "sgm"], "text/shex": ["shex"], "text/slim": ["slim", "slm"], "text/spdx": ["spdx"], "text/stylus": ["stylus", "styl"], "text/tab-separated-values": ["tsv"], "text/troff": ["t", "tr", "roff", "man", "me", "ms"], "text/turtle": ["ttl"], "text/uri-list": ["uri", "uris", "urls"], "text/vcard": ["vcard"], "text/vtt": ["vtt"], "text/xml": ["*xml"], "text/yaml": ["yaml", "yml"], "video/3gpp": ["3gp", "3gpp"], "video/3gpp2": ["3g2"], "video/h261": ["h261"], "video/h263": ["h263"], "video/h264": ["h264"], "video/iso.segment": ["m4s"], "video/jpeg": ["jpgv"], "video/jpm": ["*jpm", "jpgm"], "video/mj2": ["mj2", "mjp2"], "video/mp2t": ["ts"], "video/mp4": ["mp4", "mp4v", "mpg4"], "video/mpeg": ["mpeg", "mpg", "mpe", "m1v", "m2v"], "video/ogg": ["ogv"], "video/quicktime": ["qt", "mov"], "video/webm": ["webm"] } ```

And the following command:

esbuild --bundle ./index.ts --minify

I'm getting the following code, beautified by me to highlight the problem:

```js (() => { var p = ["ez"], t = ["aw"], l = ["atom"], m = ["atomcat"], o = ["atomdeleted"], e = ["atomsvc"], c = ["dwd"], s = ["held"], n = ["rsat"], x = ["bdoc"], d = ["xcs"], r = ["ccxml"], g = ["cdfx"], f = ["cdmia"], v = ["cdmic"], j = ["cdmid"], u = ["cdmio"], h = ["cdmiq"], b = ["cu"], k = ["mpd"], w = ["davmount"], y = ["dbk"], q = ["dssc"], z = ["xdssc"], A = ["es", "ecma"], B = ["emma"], C = ["emotionml"], D = ["epub"], E = ["exi"], F = ["exp"], G = ["fdt"], H = ["pfr"], I = ["geojson"], J = ["gml"], K = ["gpx"], L = ["gxf"], M = ["gz"], N = ["hjson"], O = ["stk"], P = ["ink", "inkml"], Q = ["ipfix"], R = ["its"], S = ["jar", "war", "ear"], T = ["ser"], U = ["class"], V = ["js", "mjs"], W = ["json", "map"], X = ["json5"], Y = ["jsonml"], Z = ["jsonld"], _ = ["lgr"], $ = ["lostxml"], ii = ["hqx"], ai = ["cpt"], pi = ["mads"], ti = ["webmanifest"], li = ["mrc"], mi = ["mrcx"], oi = ["ma", "nb", "mb"], ei = ["mathml"], ci = ["mbox"], si = ["mscml"], ni = ["metalink"], xi = ["meta4"], di = ["mets"], ri = ["maei"], gi = ["musd"], fi = ["mods"], vi = ["m21", "mp21"], ji = ["mp4s", "m4p"], ui = ["doc", "dot"], hi = ["mxf"], bi = ["nq"], ki = ["nt"], wi = ["cjs"], yi = ["bin", "dms", "lrf", "mar", "so", "dist", "distz", "pkg", "bpk", "dump", "elc", "deploy", "exe", "dll", "deb", "dmg", "iso", "img", "msi", "msp", "msm", "buffer"], qi = ["oda"], zi = ["opf"], Ai = ["ogx"], Bi = ["omdoc"], Ci = ["onetoc", "onetoc2", "onetmp", "onepkg"], Di = ["oxps"], Ei = ["relo"], Fi = ["xer"], Gi = ["pdf"], Hi = ["pgp"], Ii = ["asc", "sig"], Ji = ["prf"], Ki = ["p10"], Li = ["p7m", "p7c"], Mi = ["p7s"], Ni = ["p8"], Oi = ["ac"], Pi = ["cer"], Qi = ["crl"], Ri = ["pkipath"], Si = ["pki"], Ti = ["pls"], Ui = ["ai", "eps", "ps"], Vi = ["provx"], Wi = ["pskcxml"], Xi = ["raml"], Yi = ["rdf", "owl"], Zi = ["rif"], _i = ["rnc"], $i = ["rl"], ia = ["rld"], aa = ["rs"], pa = ["rapd"], ta = ["sls"], la = ["rusd"], ma = ["gbr"], oa = ["mft"], ea = ["roa"], ca = ["rsd"], sa = ["rss"], na = ["rtf"], xa = ["sbml"], da = ["scq"], ra = ["scs"], ga = ["spq"], fa = ["spp"], va = ["sdp"], ja = ["senmlx"], ua = ["sensmlx"], ha = ["setpay"], ba = ["setreg"], ka = ["shf"], wa = ["siv", "sieve"], ya = ["smi", "smil"], qa = ["rq"], za = ["srx"], Aa = ["gram"], Ba = ["grxml"], Ca = ["sru"], Da = ["ssdl"], Ea = ["ssml"], Fa = ["swidtag"], Ga = ["tei", "teicorpus"], Ha = ["tfi"], Ia = ["tsd"], Ja = ["toml"], Ka = ["trig"], La = ["ttml"], Ma = ["ubj"], Na = ["rsheet"], Oa = ["td"], Pa = ["vxml"], Qa = ["wasm"], Ra = ["wgt"], Sa = ["hlp"], Ta = ["wsdl"], Ua = ["wspolicy"], Va = ["xaml"], Wa = ["xav"], Xa = ["xca"], Ya = ["xdf"], Za = ["xel"], _a = ["xns"], $a = ["xenc"], ip = ["xhtml", "xht"], ap = ["xlf"], pp = ["xml", "xsl", "xsd", "rng"], tp = ["dtd"], lp = ["xop"], mp = ["xpl"], op = ["*xsl", "xslt"], ep = ["xspf"], cp = ["mxml", "xhvml", "xvml", "xvm"], sp = ["yang"], np = ["yin"], xp = ["zip"], dp = ["*3gpp"], rp = ["adp"], gp = ["amr"], fp = ["au", "snd"], vp = ["mid", "midi", "kar", "rmi"], jp = ["mxmf"], up = ["*mp3"], hp = ["m4a", "mp4a"], bp = ["mpga", "mp2", "mp2a", "mp3", "m2a", "m3a"], kp = ["oga", "ogg", "spx", "opus"], wp = ["s3m"], yp = ["sil"], qp = ["wav"], zp = ["*wav"], Ap = ["weba"], Bp = ["xm"], Cp = ["ttc"], Dp = ["otf"], Ep = ["ttf"], Fp = ["woff"], Gp = ["woff2"], Hp = ["exr"], Ip = ["apng"], Jp = ["avif"], Kp = ["bmp"], Lp = ["cgm"], Mp = ["drle"], Np = ["emf"], Op = ["fits"], Pp = ["g3"], Qp = ["gif"], Rp = ["heic"], Sp = ["heics"], Tp = ["heif"], Up = ["heifs"], Vp = ["hej2"], Wp = ["hsj2"], Xp = ["ief"], Yp = ["jls"], Zp = ["jp2", "jpg2"], _p = ["jpeg", "jpg", "jpe"], $p = ["jph"], it = ["jhc"], at = ["jpm"], pt = ["jpx", "jpf"], tt = ["jxr"], lt = ["jxra"], mt = ["jxrs"], ot = ["jxs"], et = ["jxsc"], ct = ["jxsi"], st = ["jxss"], nt = ["ktx"], xt = ["ktx2"], dt = ["png"], rt = ["sgi"], gt = ["svg", "svgz"], ft = ["t38"], vt = ["tif", "tiff"], jt = ["tfx"], ut = ["webp"], ht = ["wmf"], bt = ["disposition-notification"], kt = ["u8msg"], wt = ["u8dsn"], yt = ["u8mdn"], qt = ["u8hdr"], zt = ["eml", "mime"], At = ["3mf"], Bt = ["gltf"], Ct = ["glb"], Dt = ["igs", "iges"], Et = ["msh", "mesh", "silo"], Ft = ["mtl"], Gt = ["obj"], Ht = ["stpx"], It = ["stpz"], Jt = ["stpxz"], Kt = ["stl"], Lt = ["wrl", "vrml"], Mt = ["*x3db", "x3dbz"], Nt = ["x3db"], Ot = ["*x3dv", "x3dvz"], Pt = ["x3d", "x3dz"], Qt = ["x3dv"], Rt = ["appcache", "manifest"], St = ["ics", "ifb"], Tt = ["coffee", "litcoffee"], Ut = ["css"], Vt = ["csv"], Wt = ["html", "htm", "shtml"], Xt = ["jade"], Yt = ["jsx"], Zt = ["less"], _t = ["markdown", "md"], $t = ["mml"], il = ["mdx"], al = ["n3"], pl = ["txt", "text", "conf", "def", "list", "log", "in", "ini"], tl = ["rtx"], ll = ["*rtf"], ml = ["sgml", "sgm"], ol = ["shex"], el = ["slim", "slm"], cl = ["spdx"], sl = ["stylus", "styl"], nl = ["tsv"], xl = ["t", "tr", "roff", "man", "me", "ms"], dl = ["ttl"], rl = ["uri", "uris", "urls"], gl = ["vcard"], fl = ["vtt"], vl = ["*xml"], jl = ["yaml", "yml"], ul = ["3gp", "3gpp"], hl = ["3g2"], bl = ["h261"], kl = ["h263"], wl = ["h264"], yl = ["m4s"], ql = ["jpgv"], zl = ["*jpm", "jpgm"], Al = ["mj2", "mjp2"], Bl = ["ts"], Cl = ["mp4", "mp4v", "mpg4"], Dl = ["mpeg", "mpg", "mpe", "m1v", "m2v"], El = ["ogv"], Fl = ["qt", "mov"], Gl = ["webm"], a = { "application/andrew-inset": p, "application/applixware": t, "application/atom+xml": l, "application/atomcat+xml": m, "application/atomdeleted+xml": o, "application/atomsvc+xml": e, "application/atsc-dwd+xml": c, "application/atsc-held+xml": s, "application/atsc-rsat+xml": n, "application/bdoc": x, "application/calendar+xml": d, "application/ccxml+xml": r, "application/cdfx+xml": g, "application/cdmi-capability": f, "application/cdmi-container": v, "application/cdmi-domain": j, "application/cdmi-object": u, "application/cdmi-queue": h, "application/cu-seeme": b, "application/dash+xml": k, "application/davmount+xml": w, "application/docbook+xml": y, "application/dssc+der": q, "application/dssc+xml": z, "application/ecmascript": A, "application/emma+xml": B, "application/emotionml+xml": C, "application/epub+zip": D, "application/exi": E, "application/express": F, "application/fdt+xml": G, "application/font-tdpfr": H, "application/geo+json": I, "application/gml+xml": J, "application/gpx+xml": K, "application/gxf": L, "application/gzip": M, "application/hjson": N, "application/hyperstudio": O, "application/inkml+xml": P, "application/ipfix": Q, "application/its+xml": R, "application/java-archive": S, "application/java-serialized-object": T, "application/java-vm": U, "application/javascript": V, "application/json": W, "application/json5": X, "application/jsonml+json": Y, "application/ld+json": Z, "application/lgr+xml": _, "application/lost+xml": $, "application/mac-binhex40": ii, "application/mac-compactpro": ai, "application/mads+xml": pi, "application/manifest+json": ti, "application/marc": li, "application/marcxml+xml": mi, "application/mathematica": oi, "application/mathml+xml": ei, "application/mbox": ci, "application/mediaservercontrol+xml": si, "application/metalink+xml": ni, "application/metalink4+xml": xi, "application/mets+xml": di, "application/mmt-aei+xml": ri, "application/mmt-usd+xml": gi, "application/mods+xml": fi, "application/mp21": vi, "application/mp4": ji, "application/msword": ui, "application/mxf": hi, "application/n-quads": bi, "application/n-triples": ki, "application/node": wi, "application/octet-stream": yi, "application/oda": qi, "application/oebps-package+xml": zi, "application/ogg": Ai, "application/omdoc+xml": Bi, "application/onenote": Ci, "application/oxps": Di, "application/p2p-overlay+xml": Ei, "application/patch-ops-error+xml": Fi, "application/pdf": Gi, "application/pgp-encrypted": Hi, "application/pgp-signature": Ii, "application/pics-rules": Ji, "application/pkcs10": Ki, "application/pkcs7-mime": Li, "application/pkcs7-signature": Mi, "application/pkcs8": Ni, "application/pkix-attr-cert": Oi, "application/pkix-cert": Pi, "application/pkix-crl": Qi, "application/pkix-pkipath": Ri, "application/pkixcmp": Si, "application/pls+xml": Ti, "application/postscript": Ui, "application/provenance+xml": Vi, "application/pskc+xml": Wi, "application/raml+yaml": Xi, "application/rdf+xml": Yi, "application/reginfo+xml": Zi, "application/relax-ng-compact-syntax": _i, "application/resource-lists+xml": $i, "application/resource-lists-diff+xml": ia, "application/rls-services+xml": aa, "application/route-apd+xml": pa, "application/route-s-tsid+xml": ta, "application/route-usd+xml": la, "application/rpki-ghostbusters": ma, "application/rpki-manifest": oa, "application/rpki-roa": ea, "application/rsd+xml": ca, "application/rss+xml": sa, "application/rtf": na, "application/sbml+xml": xa, "application/scvp-cv-request": da, "application/scvp-cv-response": ra, "application/scvp-vp-request": ga, "application/scvp-vp-response": fa, "application/sdp": va, "application/senml+xml": ja, "application/sensml+xml": ua, "application/set-payment-initiation": ha, "application/set-registration-initiation": ba, "application/shf+xml": ka, "application/sieve": wa, "application/smil+xml": ya, "application/sparql-query": qa, "application/sparql-results+xml": za, "application/srgs": Aa, "application/srgs+xml": Ba, "application/sru+xml": Ca, "application/ssdl+xml": Da, "application/ssml+xml": Ea, "application/swid+xml": Fa, "application/tei+xml": Ga, "application/thraud+xml": Ha, "application/timestamped-data": Ia, "application/toml": Ja, "application/trig": Ka, "application/ttml+xml": La, "application/ubjson": Ma, "application/urc-ressheet+xml": Na, "application/urc-targetdesc+xml": Oa, "application/voicexml+xml": Pa, "application/wasm": Qa, "application/widget": Ra, "application/winhlp": Sa, "application/wsdl+xml": Ta, "application/wspolicy+xml": Ua, "application/xaml+xml": Va, "application/xcap-att+xml": Wa, "application/xcap-caps+xml": Xa, "application/xcap-diff+xml": Ya, "application/xcap-el+xml": Za, "application/xcap-ns+xml": _a, "application/xenc+xml": $a, "application/xhtml+xml": ip, "application/xliff+xml": ap, "application/xml": pp, "application/xml-dtd": tp, "application/xop+xml": lp, "application/xproc+xml": mp, "application/xslt+xml": op, "application/xspf+xml": ep, "application/xv+xml": cp, "application/yang": sp, "application/yin+xml": np, "application/zip": xp, "audio/3gpp": dp, "audio/adpcm": rp, "audio/amr": gp, "audio/basic": fp, "audio/midi": vp, "audio/mobile-xmf": jp, "audio/mp3": up, "audio/mp4": hp, "audio/mpeg": bp, "audio/ogg": kp, "audio/s3m": wp, "audio/silk": yp, "audio/wav": qp, "audio/wave": zp, "audio/webm": Ap, "audio/xm": Bp, "font/collection": Cp, "font/otf": Dp, "font/ttf": Ep, "font/woff": Fp, "font/woff2": Gp, "image/aces": Hp, "image/apng": Ip, "image/avif": Jp, "image/bmp": Kp, "image/cgm": Lp, "image/dicom-rle": Mp, "image/emf": Np, "image/fits": Op, "image/g3fax": Pp, "image/gif": Qp, "image/heic": Rp, "image/heic-sequence": Sp, "image/heif": Tp, "image/heif-sequence": Up, "image/hej2k": Vp, "image/hsj2": Wp, "image/ief": Xp, "image/jls": Yp, "image/jp2": Zp, "image/jpeg": _p, "image/jph": $p, "image/jphc": it, "image/jpm": at, "image/jpx": pt, "image/jxr": tt, "image/jxra": lt, "image/jxrs": mt, "image/jxs": ot, "image/jxsc": et, "image/jxsi": ct, "image/jxss": st, "image/ktx": nt, "image/ktx2": xt, "image/png": dt, "image/sgi": rt, "image/svg+xml": gt, "image/t38": ft, "image/tiff": vt, "image/tiff-fx": jt, "image/webp": ut, "image/wmf": ht, "message/disposition-notification": bt, "message/global": kt, "message/global-delivery-status": wt, "message/global-disposition-notification": yt, "message/global-headers": qt, "message/rfc822": zt, "model/3mf": At, "model/gltf+json": Bt, "model/gltf-binary": Ct, "model/iges": Dt, "model/mesh": Et, "model/mtl": Ft, "model/obj": Gt, "model/step+xml": Ht, "model/step+zip": It, "model/step-xml+zip": Jt, "model/stl": Kt, "model/vrml": Lt, "model/x3d+binary": Mt, "model/x3d+fastinfoset": Nt, "model/x3d+vrml": Ot, "model/x3d+xml": Pt, "model/x3d-vrml": Qt, "text/cache-manifest": Rt, "text/calendar": St, "text/coffeescript": Tt, "text/css": Ut, "text/csv": Vt, "text/html": Wt, "text/jade": Xt, "text/jsx": Yt, "text/less": Zt, "text/markdown": _t, "text/mathml": $t, "text/mdx": il, "text/n3": al, "text/plain": pl, "text/richtext": tl, "text/rtf": ll, "text/sgml": ml, "text/shex": ol, "text/slim": el, "text/spdx": cl, "text/stylus": sl, "text/tab-separated-values": nl, "text/troff": xl, "text/turtle": dl, "text/uri-list": rl, "text/vcard": gl, "text/vtt": fl, "text/xml": vl, "text/yaml": jl, "video/3gpp": ul, "video/3gpp2": hl, "video/h261": bl, "video/h263": kl, "video/h264": wl, "video/iso.segment": yl, "video/jpeg": ql, "video/jpm": zl, "video/mj2": Al, "video/mp2t": Bl, "video/mp4": Cl, "video/mpeg": Dl, "video/ogg": El, "video/quicktime": Fl, "video/webm": Gl }; var Hl = a, Kl = Hl; })(); ```

There's basically a huge number of unnecessary intermediate variables, I would have expected to find the input json basically copy/pasted in the output file, but that wasn't the case.

[hyrious]

This is because the default json loader (built-in in esbuild) turns a json file into this form:

// { "a": [42] }
export var a = [42]
export default { a }

// this guarantees that
import X, { a } from "./a.json"
X.a === a // true, is same thing (by reference)

But key names are repeated at least 2 times. In that case, you can write a plugin to alter that behavior if you only want the default export:

var MyJsonLoader = {
  name: 'my-json-loader',
  setup({ onLoad }) {
    onLoad({ filter: /\.json$/ }, async args => {
      const text = await fs.promises.readFile(args.path, 'utf8')
      return { contents: `export default ${text}` }
    })
  }
}

(I don't think this behavior should be built-in, since it requires some analysis around the usage of a json file (whether it was imported by names).

[fabiospampinato]

(I don't think this behavior should be built-in, since it requires some analysis around the usage of a json file (whether it was imported by names).

Wouldn't this be a trivial check though? It seems worth it to me, the length of the output code can get a little out of hand otherwise.

[evanw]

The reason for this is tree-shaking. For example, the following code:

export { 'application/wasm' as wasm } from './database.json'

currently bundles into the following code (with --bundle --format=esm):

```js // database.json var application_wasm = ["wasm"]; export { application_wasm as wasm }; ```

With your suggested change, you would have to do something like this instead:

import db from './database.js'
export let { 'application/wasm': wasm } = db

which would bundle into the following code (with --bundle --format=esm):

```js // database.json var database_default = { "application/andrew-inset": ["ez"], "application/applixware": ["aw"], "application/atom+xml": ["atom"], "application/atomcat+xml": ["atomcat"], "application/atomdeleted+xml": ["atomdeleted"], "application/atomsvc+xml": ["atomsvc"], "application/atsc-dwd+xml": ["dwd"], "application/atsc-held+xml": ["held"], "application/atsc-rsat+xml": ["rsat"], "application/bdoc": ["bdoc"], "application/calendar+xml": ["xcs"], "application/ccxml+xml": ["ccxml"], "application/cdfx+xml": ["cdfx"], "application/cdmi-capability": ["cdmia"], "application/cdmi-container": ["cdmic"], "application/cdmi-domain": ["cdmid"], "application/cdmi-object": ["cdmio"], "application/cdmi-queue": ["cdmiq"], "application/cu-seeme": ["cu"], "application/dash+xml": ["mpd"], "application/davmount+xml": ["davmount"], "application/docbook+xml": ["dbk"], "application/dssc+der": ["dssc"], "application/dssc+xml": ["xdssc"], "application/ecmascript": ["es", "ecma"], "application/emma+xml": ["emma"], "application/emotionml+xml": ["emotionml"], "application/epub+zip": ["epub"], "application/exi": ["exi"], "application/express": ["exp"], "application/fdt+xml": ["fdt"], "application/font-tdpfr": ["pfr"], "application/geo+json": ["geojson"], "application/gml+xml": ["gml"], "application/gpx+xml": ["gpx"], "application/gxf": ["gxf"], "application/gzip": ["gz"], "application/hjson": ["hjson"], "application/hyperstudio": ["stk"], "application/inkml+xml": ["ink", "inkml"], "application/ipfix": ["ipfix"], "application/its+xml": ["its"], "application/java-archive": ["jar", "war", "ear"], "application/java-serialized-object": ["ser"], "application/java-vm": ["class"], "application/javascript": ["js", "mjs"], "application/json": ["json", "map"], "application/json5": ["json5"], "application/jsonml+json": ["jsonml"], "application/ld+json": ["jsonld"], "application/lgr+xml": ["lgr"], "application/lost+xml": ["lostxml"], "application/mac-binhex40": ["hqx"], "application/mac-compactpro": ["cpt"], "application/mads+xml": ["mads"], "application/manifest+json": ["webmanifest"], "application/marc": ["mrc"], "application/marcxml+xml": ["mrcx"], "application/mathematica": ["ma", "nb", "mb"], "application/mathml+xml": ["mathml"], "application/mbox": ["mbox"], "application/mediaservercontrol+xml": ["mscml"], "application/metalink+xml": ["metalink"], "application/metalink4+xml": ["meta4"], "application/mets+xml": ["mets"], "application/mmt-aei+xml": ["maei"], "application/mmt-usd+xml": ["musd"], "application/mods+xml": ["mods"], "application/mp21": ["m21", "mp21"], "application/mp4": ["mp4s", "m4p"], "application/msword": ["doc", "dot"], "application/mxf": ["mxf"], "application/n-quads": ["nq"], "application/n-triples": ["nt"], "application/node": ["cjs"], "application/octet-stream": ["bin", "dms", "lrf", "mar", "so", "dist", "distz", "pkg", "bpk", "dump", "elc", "deploy", "exe", "dll", "deb", "dmg", "iso", "img", "msi", "msp", "msm", "buffer"], "application/oda": ["oda"], "application/oebps-package+xml": ["opf"], "application/ogg": ["ogx"], "application/omdoc+xml": ["omdoc"], "application/onenote": ["onetoc", "onetoc2", "onetmp", "onepkg"], "application/oxps": ["oxps"], "application/p2p-overlay+xml": ["relo"], "application/patch-ops-error+xml": ["xer"], "application/pdf": ["pdf"], "application/pgp-encrypted": ["pgp"], "application/pgp-signature": ["asc", "sig"], "application/pics-rules": ["prf"], "application/pkcs10": ["p10"], "application/pkcs7-mime": ["p7m", "p7c"], "application/pkcs7-signature": ["p7s"], "application/pkcs8": ["p8"], "application/pkix-attr-cert": ["ac"], "application/pkix-cert": ["cer"], "application/pkix-crl": ["crl"], "application/pkix-pkipath": ["pkipath"], "application/pkixcmp": ["pki"], "application/pls+xml": ["pls"], "application/postscript": ["ai", "eps", "ps"], "application/provenance+xml": ["provx"], "application/pskc+xml": ["pskcxml"], "application/raml+yaml": ["raml"], "application/rdf+xml": ["rdf", "owl"], "application/reginfo+xml": ["rif"], "application/relax-ng-compact-syntax": ["rnc"], "application/resource-lists+xml": ["rl"], "application/resource-lists-diff+xml": ["rld"], "application/rls-services+xml": ["rs"], "application/route-apd+xml": ["rapd"], "application/route-s-tsid+xml": ["sls"], "application/route-usd+xml": ["rusd"], "application/rpki-ghostbusters": ["gbr"], "application/rpki-manifest": ["mft"], "application/rpki-roa": ["roa"], "application/rsd+xml": ["rsd"], "application/rss+xml": ["rss"], "application/rtf": ["rtf"], "application/sbml+xml": ["sbml"], "application/scvp-cv-request": ["scq"], "application/scvp-cv-response": ["scs"], "application/scvp-vp-request": ["spq"], "application/scvp-vp-response": ["spp"], "application/sdp": ["sdp"], "application/senml+xml": ["senmlx"], "application/sensml+xml": ["sensmlx"], "application/set-payment-initiation": ["setpay"], "application/set-registration-initiation": ["setreg"], "application/shf+xml": ["shf"], "application/sieve": ["siv", "sieve"], "application/smil+xml": ["smi", "smil"], "application/sparql-query": ["rq"], "application/sparql-results+xml": ["srx"], "application/srgs": ["gram"], "application/srgs+xml": ["grxml"], "application/sru+xml": ["sru"], "application/ssdl+xml": ["ssdl"], "application/ssml+xml": ["ssml"], "application/swid+xml": ["swidtag"], "application/tei+xml": ["tei", "teicorpus"], "application/thraud+xml": ["tfi"], "application/timestamped-data": ["tsd"], "application/toml": ["toml"], "application/trig": ["trig"], "application/ttml+xml": ["ttml"], "application/ubjson": ["ubj"], "application/urc-ressheet+xml": ["rsheet"], "application/urc-targetdesc+xml": ["td"], "application/voicexml+xml": ["vxml"], "application/wasm": ["wasm"], "application/widget": ["wgt"], "application/winhlp": ["hlp"], "application/wsdl+xml": ["wsdl"], "application/wspolicy+xml": ["wspolicy"], "application/xaml+xml": ["xaml"], "application/xcap-att+xml": ["xav"], "application/xcap-caps+xml": ["xca"], "application/xcap-diff+xml": ["xdf"], "application/xcap-el+xml": ["xel"], "application/xcap-ns+xml": ["xns"], "application/xenc+xml": ["xenc"], "application/xhtml+xml": ["xhtml", "xht"], "application/xliff+xml": ["xlf"], "application/xml": ["xml", "xsl", "xsd", "rng"], "application/xml-dtd": ["dtd"], "application/xop+xml": ["xop"], "application/xproc+xml": ["xpl"], "application/xslt+xml": ["*xsl", "xslt"], "application/xspf+xml": ["xspf"], "application/xv+xml": ["mxml", "xhvml", "xvml", "xvm"], "application/yang": ["yang"], "application/yin+xml": ["yin"], "application/zip": ["zip"], "audio/3gpp": ["*3gpp"], "audio/adpcm": ["adp"], "audio/amr": ["amr"], "audio/basic": ["au", "snd"], "audio/midi": ["mid", "midi", "kar", "rmi"], "audio/mobile-xmf": ["mxmf"], "audio/mp3": ["*mp3"], "audio/mp4": ["m4a", "mp4a"], "audio/mpeg": ["mpga", "mp2", "mp2a", "mp3", "m2a", "m3a"], "audio/ogg": ["oga", "ogg", "spx", "opus"], "audio/s3m": ["s3m"], "audio/silk": ["sil"], "audio/wav": ["wav"], "audio/wave": ["*wav"], "audio/webm": ["weba"], "audio/xm": ["xm"], "font/collection": ["ttc"], "font/otf": ["otf"], "font/ttf": ["ttf"], "font/woff": ["woff"], "font/woff2": ["woff2"], "image/aces": ["exr"], "image/apng": ["apng"], "image/avif": ["avif"], "image/bmp": ["bmp"], "image/cgm": ["cgm"], "image/dicom-rle": ["drle"], "image/emf": ["emf"], "image/fits": ["fits"], "image/g3fax": ["g3"], "image/gif": ["gif"], "image/heic": ["heic"], "image/heic-sequence": ["heics"], "image/heif": ["heif"], "image/heif-sequence": ["heifs"], "image/hej2k": ["hej2"], "image/hsj2": ["hsj2"], "image/ief": ["ief"], "image/jls": ["jls"], "image/jp2": ["jp2", "jpg2"], "image/jpeg": ["jpeg", "jpg", "jpe"], "image/jph": ["jph"], "image/jphc": ["jhc"], "image/jpm": ["jpm"], "image/jpx": ["jpx", "jpf"], "image/jxr": ["jxr"], "image/jxra": ["jxra"], "image/jxrs": ["jxrs"], "image/jxs": ["jxs"], "image/jxsc": ["jxsc"], "image/jxsi": ["jxsi"], "image/jxss": ["jxss"], "image/ktx": ["ktx"], "image/ktx2": ["ktx2"], "image/png": ["png"], "image/sgi": ["sgi"], "image/svg+xml": ["svg", "svgz"], "image/t38": ["t38"], "image/tiff": ["tif", "tiff"], "image/tiff-fx": ["tfx"], "image/webp": ["webp"], "image/wmf": ["wmf"], "message/disposition-notification": ["disposition-notification"], "message/global": ["u8msg"], "message/global-delivery-status": ["u8dsn"], "message/global-disposition-notification": ["u8mdn"], "message/global-headers": ["u8hdr"], "message/rfc822": ["eml", "mime"], "model/3mf": ["3mf"], "model/gltf+json": ["gltf"], "model/gltf-binary": ["glb"], "model/iges": ["igs", "iges"], "model/mesh": ["msh", "mesh", "silo"], "model/mtl": ["mtl"], "model/obj": ["obj"], "model/step+xml": ["stpx"], "model/step+zip": ["stpz"], "model/step-xml+zip": ["stpxz"], "model/stl": ["stl"], "model/vrml": ["wrl", "vrml"], "model/x3d+binary": ["*x3db", "x3dbz"], "model/x3d+fastinfoset": ["x3db"], "model/x3d+vrml": ["*x3dv", "x3dvz"], "model/x3d+xml": ["x3d", "x3dz"], "model/x3d-vrml": ["x3dv"], "text/cache-manifest": ["appcache", "manifest"], "text/calendar": ["ics", "ifb"], "text/coffeescript": ["coffee", "litcoffee"], "text/css": ["css"], "text/csv": ["csv"], "text/html": ["html", "htm", "shtml"], "text/jade": ["jade"], "text/jsx": ["jsx"], "text/less": ["less"], "text/markdown": ["markdown", "md"], "text/mathml": ["mml"], "text/mdx": ["mdx"], "text/n3": ["n3"], "text/plain": ["txt", "text", "conf", "def", "list", "log", "in", "ini"], "text/richtext": ["rtx"], "text/rtf": ["*rtf"], "text/sgml": ["sgml", "sgm"], "text/shex": ["shex"], "text/slim": ["slim", "slm"], "text/spdx": ["spdx"], "text/stylus": ["stylus", "styl"], "text/tab-separated-values": ["tsv"], "text/troff": ["t", "tr", "roff", "man", "me", "ms"], "text/turtle": ["ttl"], "text/uri-list": ["uri", "uris", "urls"], "text/vcard": ["vcard"], "text/vtt": ["vtt"], "text/xml": ["*xml"], "text/yaml": ["yaml", "yml"], "video/3gpp": ["3gp", "3gpp"], "video/3gpp2": ["3g2"], "video/h261": ["h261"], "video/h263": ["h263"], "video/h264": ["h264"], "video/iso.segment": ["m4s"], "video/jpeg": ["jpgv"], "video/jpm": ["*jpm", "jpgm"], "video/mj2": ["mj2", "mjp2"], "video/mp2t": ["ts"], "video/mp4": ["mp4", "mp4v", "mpg4"], "video/mpeg": ["mpeg", "mpg", "mpe", "m1v", "m2v"], "video/ogg": ["ogv"], "video/quicktime": ["qt", "mov"], "video/webm": ["webm"] }; // index.ts var { "application/wasm": wasm } = database_default; export { wasm }; ```

There's probably something I can do to make this more efficient when only the default export ends up being used. But only exposing the default export would be a regression in functionality for tree shaking. As you can see with this example, it would be quite a big size regression in some cases.

[fabiospampinato]

Makes sense, it's not as simple as I naively thought 🤔 Still it's probably worth addressing eventually.